Resist composition and method for producing resist pattern

Abstract

To provide a resist composition from which a resist pattern having good CD uniformity can be produced.SOLUTION: A resist composition contains: an acid generator containing a salt represented by a formula (I); and a resin containing a structural unit represented by a specific formula and a structural unit having an acid-labile group. [In the formula (I), X represents an S atom or an I atom; and AI- represents an organic anion.]SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resist composition and a method for producing a resist pattern using the resist composition.

Background Art

[0002] Patent Document 1 describes a resist composition containing an acid generator represented by the following formula and a resin containing the following structural unit. TIFF2025091391000001.tif78147

[0003] Patent Document 2 describes a resist composition containing an acid generator represented by the following formula. TIFF2025091391000002.tif3054

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention provides a resist composition that forms a resist pattern having better CD uniformity (CDU) than a resist pattern formed by the above resist composition.

Means for Solving the Problems

[0006] The present invention includes the following inventions. 〔1〕A resist composition containing an acid generator containing a salt represented by formula (I) and a resin containing a structural unit represented by formula (II) and a structural unit having an acid-labile group. TIFF2025091391000003.tif62150[In formula (I), X represents a sulfur atom or an iodine atom. m10 represents 0 or 1. When X is a sulfur atom, m10 is 1; when X is an iodine atom, m10 is 0. R 1 、R 2 and R 3 each independently represent a linear alkyl group having 2 to 12 carbon atoms. R 4 、R 5 and R 6 each independently represent a halogen atom or a hydrocarbon group having 1 to 18 carbon atoms. The hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S-, -SO- or -SO2-. R 7 、R 8 and R 9 each independently represent a halogen atom or a hydrocarbon group having 1 to 18 carbon atoms. The hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S-, -SO- or -SO2-. Further, when X is a sulfur atom, R 7 and R 8 or R 8 and R 9 may combine to form a ring containing S + . -CH2- contained in the ring may be replaced by -O-, -S-, -CO-, -SO- or -SO2-. R 7 and R 8 or R 8 and R 9 that form the ring may be a single bond formed between two benzene rings bonded to S + . A 1 、A 2 and A 3 each independently represent a single bond or a hydrocarbon group having 1 to 20 carbon atoms. The hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. Ar1 and Ar 2 and Ar 3 each independently represents an aromatic hydrocarbon group having 6 to 10 carbon atoms or a heteroaromatic hydrocarbon group having 4 to 9 carbon atoms. m1 represents any integer from 0 to 5. When m1 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. m2 represents any integer from 0 to 5. When m2 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. m3 represents any integer from 0 to 5. When m3 is 2 or more, the groups within multiple parentheses may be the same as or different from each other. m4 represents any integer from 0 to 4. When m4 is 2 or more, the multiple Rs 4 may be the same as or different from each other. m5 represents any integer from 0 to 4. When m5 is 2 or more, the multiple Rs 5 may be the same as or different from each other. m6 represents any integer from 0 to 4. When m6 is 2 or more, the multiple Rs 6 may be the same as or different from each other. m7 represents any integer from 0 to 5. When m7 is 2 or more, the multiple Rs 7 may be the same as or different from each other. m8 represents any integer from 0 to 5. When m8 is 2 or more, the multiple Rs 8 may be the same as or different from each other. m9 represents any integer from 0 to 5. When m9 is 2 or more, the multiple Rs 9 may be the same as or different from each other. However, 1 ≦ m1 + m7 ≦ 5, 1 ≦ m2 + m8 ≦ 5, 1 ≦ m3 + m9 ≦ 5. When m1 = m2 = m3 = 0, R 7 , R 8 and R 9 represent a linear alkyl group having 2 to 12 carbon atoms. AI - represents an organic anion. TIFF2025091391000004.tif2675 [In formula (II), R 12 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. L 11 represents a single bond or *-L 2 -CO-O-(L 3 -CO-O) g -. * represents the bonding site with the oxygen atom. L 2 and L 3 each independently represent a divalent hydrocarbon group having 1 to 12 carbon atoms. g represents 0 or 1. R 13 represents a linear alkyl group having 2 to 12 carbon atoms. 〔2〕A 1 is **-X 01 -L 01 - or **-L 01 -X 01 -, A 2 is **-X 02 -L 02 - or **-L 02 -X 02 -, A 3 is **-X 03 -L 03 - or **-L 03 -X 03 -, X 01 , X 02 and X 03 each independently represent -O-, -CO-, -S- or -SO2-, L 01 , L 02 and L 03 each independently represent a single bond or a hydrocarbon group having 1 to 18 carbon atoms (the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-). ** represents the bonding site with the benzene ring to which X + is bonded. The resist composition according to [1]. 〔3〕X 01 , X 02 and X 03The resist composition according to [2], wherein each is independently -O- or -S-. [4] L 01 , L 02 and L 03 The resist composition according to [2] or [3], wherein each is independently a single bond or an alkanediyl group having 1 to 6 carbon atoms (the -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-). [5] The resist composition according to any one of [1] to [4], wherein X is a sulfur atom. [6] Ar 1 , Ar 2 and Ar 3 The resist composition according to any one of [1] to [5], wherein each is independently a group derived from a benzene ring, a naphthalene ring, a furan ring or a thiophene ring. [7] L 11 The resist composition according to any one of [1] to [6], wherein L is a single bond. [8] R 13 The resist composition according to any one of [1] to [7], wherein R is a linear alkyl group having 3 to 8 carbon atoms. [9] The resist composition according to any one of [1] to [8], wherein the structural unit having an acid-labile group contains at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), a structural unit represented by formula (a1-2), a structural unit represented by formula (a1-4), a structural unit represented by formula (a1-5) and a structural unit represented by formula (a1-6). TIFF2025091391000005.tif44140[In formula (a1-0), formula (a1-1) and formula (a1-2), L a01 , L a1 and L a2 each independently represents -O- or *-O-(CH2) k1 -CO-O-, k1 represents an integer of 1 to 7, and * represents the bonding site to -CO-. R a01 , R a4 and R a5Each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a02 , R a03 and R a04 each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. R a6 and R a7 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. m1 represents any integer from 0 to 14. n1 represents any integer from 0 to 10. n1’ represents any integer from 0 to 3. TIFF2025091391000006.tif31118[In formula (a1-4), R a1 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a17 represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A a11 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO-, or -NR a18 -. R a18represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a1 represents a single bond or a carbonyl group. R a34 and R a35 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and the -CH2- contained in the hydrocarbon group and the divalent hydrocarbon group may be replaced by -O- or -S-. na1 represents any integer from 1 to 5. When na1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. na11 represents any integer from 0 to 4. When na11 is 2 or more, the plurality of R a17 may be the same as or different from each other. mc represents any integer from 0 to 2. TIFF2025091391000007.tif4558[In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. Z a1 represents a single bond or *-(CH2) h3 -CO-L 54 -, h3 represents any integer from 1 to 4, and * represents the bonding site with L 51 L 51 L 52 L 53 and L 54 each independently represent -O- or -S-. s1 represents any integer from 1 to 3. s1’ represents any integer from 0 to 3. TIFF2025091391000008.tif3681[In formula (a1-6), R a61 ​represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a62 , R a63 and R a64 each independently represent an alkyl group having 1 to 6 carbon atoms or a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or R a62 and R a63 are bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded. X a61 represents a single bond, -CO-O-*, or -CO-NR a65 -*, where * represents the bonding site to Ar, and R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 represents a single bond, *-O-L a61 -, or *-CO-O-L a62 -, where * represents the bonding site to Ar, and L a61 and L a62 each independently represent an alkanediyl group having 1 to 4 carbon atoms. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. [

[10] ] AI - is the resist composition according to any one of [[1]] to [[9]], wherein AI is an anion represented by formula (I-A). [In formula (I-A), L b1 represents a single bond or a (nb1 + 1)-valent hydrocarbon group which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, or -SO2-. L b2 represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO-, or -SO2-. Y b1represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. nb1 represents any integer from 1 to 6. When nb1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. 〔11〕The resist composition according to any one of 〔1〕~〔10〕, further containing a salt that generates an acid having a lower acidity than the acid generated from the acid generator. 〔12〕(1) A step of applying the resist composition according to any one of 〔1〕~〔11〕 onto a substrate, (2) A step of drying the applied resist composition to form a composition layer, (3) A step of exposing the composition layer, (4) A step of heating the exposed composition layer, and (5) A step of developing the heated composition layer, which is a method for manufacturing a resist pattern.

Advantages of the Invention

[0007] By using the resist composition of the present invention, a resist pattern can be manufactured with good CD uniformity (CDU).

Modes for Carrying Out the Invention

[0008] As used herein, the term "(meth)acrylic monomer" means "at least one of acrylic monomers and methacrylic monomers". The notations such as "(meth)acrylate" and "(meth)acrylic acid" also represent the same meaning. Among the groups described in this specification, those that can take both a linear structure and a branched structure may be either of them. When -CH2- contained in a hydrocarbon group or the like is replaced by -O-, -S-, -CO- or -SO2- or the like, the same examples are applied to each group, and the number of carbon atoms before replacement is defined as the number of carbon atoms of the hydrocarbon group or the like. The term "combined group" means a group formed by bonding two or more of the exemplified groups, and their valences may be appropriately changed depending on the bonding form. The term "derived from" or "derived" refers to the fact that the polymerizable C=C bond contained in the molecule becomes a single bond (-C-C- group) by polymerization. When stereoisomers exist, all stereoisomers are included. An acid-labile group means a group that, when contacted with an acid (e.g., trifluoromethanesulfonic acid), the leaving group leaves to form a hydrophilic group (e.g., a hydroxy group or a carboxy group). A base-labile group means a group that, when contacted with a base (e.g., trimethylamine), the leaving group leaves to form a hydrophilic group (e.g., a carboxy group or a hydroxy group). Each group may have any position and number of hydrogen atoms contained in the group replaced by a bonding site depending on the number of substituents and the like. The number of carbon atoms in the substituent is not included in the number of carbon atoms of the group to be substituted. As used herein, the "solid content of the resist composition" means the total of the components excluding the solvent (E) described below from the total amount of the resist composition.

[0009] [Resist Composition] The resist composition of the present invention contains an acid generator containing a salt represented by formula (I) and a resin containing a structural unit represented by formula (II) and a structural unit having an acid-labile group. As used herein, the term "acid-labile group" means a group having a leaving group that leaves upon contact with an acid to form a hydrophilic group (e.g., a hydroxy group or a carboxy group). The resist composition of the present invention preferably contains a quencher such as a salt that generates an acid having a weaker acidity than the acid generated from the acid generator (hereinafter may be referred to as "quencher (C)"), and preferably contains a solvent (hereinafter may be referred to as "solvent (E)").

[0010] <Salt represented by formula (I)> The present invention relates to a salt represented by formula (I) (hereinafter sometimes referred to as "salt (I)"). In the salt (I), the side having a positive charge is sometimes called the "cation (I)" and the side having a negative charge is sometimes called the "anion (I)".

[0011] [Cation (I)] The cation (I) of the salt represented by formula (I) is a cation represented by formula (IC). TIFF2025091391000010.tif62158 [In formula (IC), all symbols have the same meaning as in formula (I)]

[0012] R 1 , R 2 and R 3 Examples of the linear alkyl group having 2 to 12 carbon atoms include an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, and an n-dodecyl group, etc. The number of carbon atoms in the alkyl group is preferably 2 to 10, more preferably 2 to 8, further preferably 2 to 6, and further preferably 3 to 6.

[0013] R 4 , R 5 , R 6 , R 7 , R 8 and R 9 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 4 , R 5 , R 6 , R 7 , R 8 and R 9Examples of the hydrocarbon group having 1 to 18 carbon atoms include a chain hydrocarbon group such as an alkyl group or an alkanediyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these. The alkyl group is a linear or branched alkyl group. Examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, and a dodecyl group. The number of carbon atoms of the alkyl group is preferably 1 to 12, more preferably 1 to 9, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The alkanediyl group is a linear or branched alkanediyl group, and examples thereof include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, and a hexane-1,6-diyl group; and branched alkanediyl groups such as an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a pentane-2,4-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. The number of carbon atoms of the chain hydrocarbon group is preferably 1 to 12, more preferably 1 to 9, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The alicyclic hydrocarbon group may be monocyclic or polycyclic, and examples thereof include the groups represented below. The bonding site can be at any position. TIFF2025091391000011.tif46168Specifically, examples of the monocyclic alicyclic hydrocarbon group include monocyclic cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, cyclododecyl group, etc. Examples of the polycyclic alicyclic hydrocarbon group include polycyclic cycloalkyl groups such as decahydronaphthyl group, adamantyl group, norbornyl group, cycloalkyl groups such as spirocyclohexane-1,2'-cyclopentane group, spiroadamantane-2,3'-cyclopentane group, and spiro rings having a cycloalkyl group bonded spiro to each of the norbornyl group or adamantyl group. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, and even more preferably 3 to 12. Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, biphenyl group, anthryl group, phenanthryl group, binaphthyl group, etc. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 18, more preferably 6 to 14, and even more preferably 6 to 10.

[0014] Among the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group, examples of the group formed by combining two or more of these groups include a group formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group (for example, aromatic hydrocarbon group - alkane diyl group - *, alkyl group - aromatic hydrocarbon group - *, alkyl group - aromatic hydrocarbon group - alkane diyl group - *, and -CH2- contained in the alkane diyl group and the alkyl group may be replaced by -O-, -CO-, -S-, -SO- or -SO2-. The alkane diyl group is a group obtained by removing one hydrogen atom from the above-mentioned alkyl group.), a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group (for example, alicyclic hydrocarbon group - alkane diyl group - *, alkyl group - alicyclic hydrocarbon group - *, alkyl group - alicyclic hydrocarbon group - alkane diyl group - *, and -CH2- contained in the alicyclic hydrocarbon group, the alkane diyl group and the alkyl group may be replaced by -O-, -CO-, -S-, -SO- or -SO2-), and a group formed by combining an aromatic hydrocarbon group and an alicyclic hydrocarbon group (for example, aromatic hydrocarbon group - alicyclic hydrocarbon group - *, alicyclic hydrocarbon group - aromatic hydrocarbon group - *, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-). * represents a bonding site. Examples of the aromatic hydrocarbon group - alkane diyl group - * include aralkyl groups such as benzyl group and phenethyl group. Examples of the alkyl group - aromatic hydrocarbon group - * include tolyl group, xylyl group, cumenyl group and the like. Examples of the alicyclic hydrocarbon group - alkane diyl group - * include cycloalkylalkyl groups such as cyclohexylmethyl group, cyclohexylethyl group, 1-(adamantan-1-yl)methyl group, 1-(adamantan-1-yl)-1-methylethyl group and the like. Examples of the alkyl group - alicyclic hydrocarbon group - * include cycloalkyl groups having an alkyl group such as methylcyclohexyl group, dimethylcyclohexyl group, 2-alkyladamantan-2-yl group and the like. Examples of the aromatic hydrocarbon group - alicyclic hydrocarbon group - * include phenylcyclohexyl group and the like. Examples of the alicyclic hydrocarbon group - aromatic hydrocarbon group - * include a cyclohexylphenyl group and the like. In the combination, two or more kinds of alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and chain hydrocarbon groups may be combined with each other. Further, any of the groups may be bonded to Ar 1 Ar 2 Ar 3 or a benzene ring.

[0015] R 4 R 5 R 6 R 7 R 8 and R 9 When -CH2- contained in the hydrocarbon group represented by is replaced by -O-, -CO-, -S-, -SO- or -SO2-, the number of carbon atoms before replacement is defined as the total number of carbon atoms of the hydrocarbon group. Further, the number may be one or two or more. Examples of groups in which -CH2- contained in a hydrocarbon group is replaced by -O-, -CO-, -S-, -SO- or -SO2- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a thiol group (a group in which -CH2- contained in a methyl group is replaced by -S-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an alkoxycarbonyloxy group (a group in which -CH2-CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-O-), an alkylthio group (a group in which -CH2- at any position contained in an alkyl group is replaced by -S-), an alkylsulfinyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -SO-), an alkylsulfonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -SO2-), an oxy group (a group in which -CH2- contained in a methylene group is replaced by -O-), a carbonyl group (a group in which -CH2- contained in a methylene group is replaced by -CO-), a thio group (a group in which -CH2- contained in a methylene group is replaced by -S-), a sulfinyl group (a group in which -CH2- contained in a methylene group is replaced by -SO-), a sulfonyl group (a group in which -CH2- contained in a methylene group is replaced by -SO2-), an alkanediyl-oxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -O-), an alkanediyl-oxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -O-CO-), an alkanediyl-carbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -CO-), an alkanediyl-carbonyl-oxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is-CO-O-replaced group), an alkanediylthio group (a group in which any -CH2- in the alkanediyl group is replaced by -S-), an alkanediylsulfinyl group (a group in which any -CH2- in the alkanediyl group is replaced by -SO-), an alkanediylsulfonyl group (a group in which any -CH2- in the alkanediyl group is replaced by -SO2-), a cycloalkoxy group, a cycloalkylalkoxy group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, a group formed by combining two or more of these groups, and the like can be mentioned. Examples of the alkoxy group include alkoxy groups having 1 to 17 carbon atoms, such as methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, octyloxy group, 2-ethylhexyloxy group, nonyloxy group, decyloxy group, undecyloxy group and the like. The number of carbon atoms of the alkoxy group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 17 carbon atoms, such as a methoxycarbonyl group, an ethoxycarbonyl group, and a butoxycarbonyl group. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 18 carbon atoms, such as an acetyl group, a propionyl group, and a butyryl group. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 17 carbon atoms, such as an acetyloxy group, a propionyloxy group, and a butyryloxy group. Examples of the alkoxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 16 carbon atoms, such as a butoxycarbonyloxy group. The number of carbon atoms of the alkoxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkoxycarbonyloxy group is preferably 2 to 10, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkylthio group include alkylthio groups having 1 to 17 carbon atoms, such as a methylthio group, an ethylthio group, a propylthio group, a butylthio group, a pentylthio group, a hexylthio group, an octylthio group, a 2-ethylhexylthio group, a nonylthio group, a decylthio group, and an undecylthio group. The number of carbon atoms of the alkylthio group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkylsulfuryl group include alkylsulfuryl groups having 1 to 17 carbon atoms, such as methylsulfuryl group, ethylsulfuryl group, propylsulfuryl group, butylsulfuryl group, pentylsulfuryl group, hexylsulfuryl group, octylsulfuryl group, 2-ethylhexylsulfuryl group, nonylsulfuryl group, decylsulfuryl group, undecylsulfuryl group, etc. The number of carbon atoms of the alkylsulfuryl group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 17 carbon atoms, such as methylsulfonyl group, ethylsulfonyl group, propylsulfonyl group, butylsulfonyl group, pentylsulfonyl group, hexylsulfonyl group, octylsulfonyl group, 2-ethylhexylsulfonyl group, nonylsulfonyl group, decylsulfonyl group, undecylsulfonyl group, etc. The number of carbon atoms of the alkylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanedioxy group include alkanedioxy groups having 1 to 17 carbon atoms, such as methyleneoxy group, ethyleneoxy group, propanedioxy group, butanedioxy group, pentanedioxy group, etc. The number of carbon atoms of the alkanedioxy group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl oxycarbonyl group include alkanediyl oxycarbonyl groups having 2 to 17 carbon atoms, such as a methylene oxycarbonyl group, an ethylene oxycarbonyl group, a propanediyl oxycarbonyl group, and a butanediyl oxycarbonyl group. Examples of the alkanediyl carbonyl group include alkanediyl carbonyl groups having 2 to 18 carbon atoms, such as a methylene carbonyl group, an ethylene carbonyl group, a propanediyl carbonyl group, a butanediyl carbonyl group, and a pentanediyl carbonyl group. Examples of the alkanediyl carbonyloxy group include alkanediyl carbonyloxy groups having 2 to 17 carbon atoms, such as a methylene carbonyloxy group, an ethylene carbonyloxy group, a propanediyl carbonyloxy group, and a butanediyl carbonyloxy group. The number of carbon atoms in the alkanediyl oxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediyl carbonyl group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediyl carbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkanediyl thio group include alkanediyl thio groups having 1 to 17 carbon atoms, such as a methylene thio group, an ethylene thio group, and a propylene thio group. The number of carbon atoms in the alkanediyl thio group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl sulfinyl group include alkanediyl sulfinyl groups having 1 to 17 carbon atoms, such as a methylene sulfinyl group, an ethylene sulfinyl group, and a propylene sulfinyl group. The number of carbon atoms in the alkanediyl sulfinyl group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediylsulfonyl group include alkanediylsulfonyl groups having 1 to 17 carbon atoms, such as a methylenesulfonyl group, an ethylenesulfonyl group, and a propylenesulfonyl group. The number of carbon atoms of the alkanediylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the cycloalkoxy group include cycloalkoxy groups having 3 to 17 carbon atoms, such as a cyclohexyloxy group. Examples of the cycloalkylalkoxy group include cycloalkylalkoxy groups having 4 to 17 carbon atoms, such as a cyclohexylmethoxy group. Examples of the aromatic hydrocarbon group-carbonyl-oxy group include aromatic hydrocarbon group-carbonyl-oxy groups having 7 to 17 carbon atoms, such as a benzoyloxy group. Examples of the aromatic hydrocarbon group-carbonyl group include aromatic hydrocarbon group-carbonyl groups having 7 to 18 carbon atoms, such as a benzoyl group. Examples of the aromatic hydrocarbon group-oxy group include aromatic hydrocarbon group-oxy groups having 6 to 17 carbon atoms, such as a phenyloxy group.

[0016] In addition, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include the groups represented below. -O- or -CO- in the groups represented below may be replaced by -S- or -SO2-. The bonding site can be at any position. Examples of the group in which -CH2- contained in the group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- also include the following groups. The bonding site can be at any position. TIFF2025091391000013.tif26164

[0017] R 4 、R 5 、R 6 、R 7 、R 8 and R9 Examples of the substituent that the hydrocarbon group may have include a halogen atom and a cyano group. Examples of the halogen atom include the same groups as those described above. R 4 、R 5 、R 6 、R 7 、R 8 and R 9 When R 4 、R 5 、R 6 、R 7 、R 8 and R 9 are hydrocarbon groups having a halogen atom, examples of the hydrocarbon groups having a halogen atom of R 、R 、R include chain hydrocarbon groups having a halogen atom such as haloalkyl groups, alicyclic hydrocarbon groups having a halogen atom, and aromatic hydrocarbon groups having a halogen atom. Examples of the alkyl group having a halogen atom include C1-C12 fluoroalkyl groups, C1-C12 chloroalkyl groups, C1-C12 bromoalkyl groups, C1-C12 iodoalkyl groups and other C1-C12 haloalkyl groups. Examples of the haloalkyl group include C1-C12 perfluoroalkyl groups (trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, nonafluorobutyl group, etc.), 2,2,2-trifluoroethyl group, 3,3,3-trifluoropropyl group, 4,4,4-trifluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, chloromethyl group, bromomethyl group, iodomethyl group, etc. The number of carbon atoms of the haloalkyl group is preferably 1-9, more preferably 1-6, still more preferably 1-4, and even more preferably 1-3.The -CH2- contained in the haloalkyl group may be replaced by -O- or -CO-, and examples of such groups include haloalkoxy groups, haloalkoxycarbonyl groups, haloalkylcarbonyl groups, haloalkylcarbonyloxy groups, etc. Specific examples include haloalkoxy groups having 1 to 11 carbon atoms, haloalkoxycarbonyl groups having 2 to 11 carbon atoms, haloalkylcarbonyl groups having 2 to 12 carbon atoms, haloalkylcarbonyloxy groups having 2 to 11 carbon atoms, etc., and examples thereof include groups in which one or more hydrogen atoms of the above-exemplified groups are replaced by halogen atoms. The hydrocarbon group may have one substituent or multiple substituents.

[0018] R 4 , R 5 and R 6 are each independently preferably a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the haloalkyl group and the alkyl group may be replaced with -O- or -CO-), more preferably an iodine atom, a fluorine atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 8 carbon atoms (-CH2- contained in the haloalkyl group and the alkyl group may be replaced with -O- or -CO-), and more preferably an iodine atom, a fluorine atom, a haloalkyl group having 1 to 4 carbon atoms, or an alkyl group having 1 to 6 carbon atoms (-CH2- contained in the alkyl group may be replaced with -O- or -CO-). (which may be substituted). It is more preferable that it is an iodine atom, a fluorine atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, a haloalkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, it is even more preferable that it is an iodine atom, a fluorine atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, a perfluoroalkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, it is even more preferable that it is an iodine atom, a fluorine atom, a trifluoromethyl group, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, a methoxy group, an ethoxy group, or a hydroxy group.

[0019] R 7 , R8 and R 9 are each independently preferably a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 12 carbon atoms (-CH2- contained in the haloalkyl group and the alkyl group may be replaced by -O- or -CO-), more preferably a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 8 carbon atoms (-CH2- contained in the haloalkyl group and the alkyl group may be replaced by -O- or -CO-), and more preferably a halogen atom, a fluorinated alkyl group having 1 to 4 carbon atoms, or an alkyl group having 1 to 6 carbon atoms (the alkyl group may be replaced by -O- or -CO-).

[0046] The alkyl group is preferably a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 4 carbon atoms, or an alkyl group having 1 to 6 carbon atoms (wherein the -CH2- contained in the alkyl group may be replaced by -O- or -CO-), and more preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a hydroxy group, a methoxy group, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, or a t-butyl group.

[0020] Ar 1 , Ar 2 and Ar 3 Examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms include groups derived from a benzene ring or a naphthalene ring, such as a phenylene group or a naphthylene group. 1 , Ar 2 and Ar 3 Examples of the heterocyclic aromatic hydrocarbon group having 4 to 9 carbon atoms include groups derived from a furan ring, a thiophene ring, a benzofuran ring, a benzothiophene ring, or the like. Ar 1 , Ar 2 and Ar 3 are each independently preferably a group derived from a benzene ring, a naphthalene ring, a furan ring, or a thiophene ring, and more preferably a group derived from a benzene ring.

[0021] A 1 , A2 and A 3 Examples of the hydrocarbon group of 3 include linear or branched chain hydrocarbon groups (e.g., alkanediyl groups, etc.), monocyclic or polycyclic alicyclic hydrocarbon groups, and aromatic hydrocarbon groups, and those obtained by combining two or more of these groups may also be used. The number of carbon atoms in the hydrocarbon group is preferably 1 to 19, more preferably 1 to 18, still more preferably 1 to 16, even more preferably 1 to 14, and even more preferably 1 to 12. Examples of the chain hydrocarbon group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, and heptadecane-1,17-diyl group, and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 18, more preferably 1 to 12, still more preferably 1 to 9, even more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. The alicyclic hydrocarbon group may be either monocyclic or polycyclic, and examples thereof include the groups represented below. The bonding site can be at any position. TIFF2025091391000014.tif46168 Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group, etc., which are monocyclic cycloalkanediyl groups, and polycyclic alicyclic hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc., which are polycyclic cycloalkanediyl groups, cycloalkyl groups such as spirocyclohexane-1,2'-cyclopentane group, spiroadamantane-2,3'-cyclopentane group, etc., and spiro rings having a cycloalkyl group spiro-bonded to a norbornyl group or an adamantyl group, respectively. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 16, still more preferably 3 to 12, and even more preferably 3 to 10. Examples of the aromatic hydrocarbon group include arylene groups such as phenylene group, naphthylene group, anthrylene group, biphenylene group, phenanthrylene group, etc. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 18, more preferably 6 to 14, and still more preferably 6 to 10.

[0022] Examples of the group formed by combination include a group formed by combining an alicyclic hydrocarbon group and an alkanediyl group, a group formed by combining an aromatic hydrocarbon group and an alkanediyl group, and a group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group. In the combination, two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group may be combined. Also, any group may be bonded to the benzene ring. Examples of the group formed by combining an alicyclic hydrocarbon group and an alkanediyl group include, for example, -divalent alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent alicyclic hydrocarbon group-, etc. Examples of groups combining an aromatic hydrocarbon group and an alkanediyl group include -divalent aromatic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent aromatic hydrocarbon group-alkanediyl group-, -alkanediyl group-divalent aromatic hydrocarbon group-, and the like. Examples of groups combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group include -aromatic hydrocarbon group-alicyclic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-, -alicyclic hydrocarbon group-aromatic hydrocarbon group-, and -alicyclic hydrocarbon group-aromatic hydrocarbon group-alicyclic hydrocarbon group-.

[0023] A 1 , A 2 and A 3 In the case where -CH2- in the hydrocarbon group is replaced with -O-, -CO-, -S- or -SO2-, the number of carbon atoms before the replacement is regarded as the total number of carbon atoms in the hydrocarbon group. The number may be 1 or 2 or more, but is preferably 1 or 2. Examples of groups in which -CH2- contained in a hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- contained in a methyl group is replaced by -S-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an alkoxycarbonyloxy group (a group in which -CH2-CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-O-), an alkylthio group (a group in which -CH2- at any position contained in an alkyl group is replaced by -S-), an alkylsulfonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -SO2-), an oxy group (a group in which -CH2- contained in a methylene group is replaced by -O-), a carbonyl group (a group in which -CH2- contained in a methylene group is replaced by -CO-), a thio group (a group in which -CH2- contained in a methylene group is replaced by -S-), a sulfonyl group (a group in which -CH2- contained in a methylene group is replaced by -SO2-), an alkanedioxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -CO-O-), an alkanediylsulfonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -SO2-),An alkanediylthio group (a group in which any -CH2- in the alkanediyl group is replaced by -S-), a cycloalkoxy group, a cycloalkylalkoxy group, an aromatic hydrocarbon group-carbonyloxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, a group formed by combining two or more of these groups, and the like can be mentioned. Examples of the alkoxy group include alkoxy groups having 1 to 19 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group, and the like. The number of carbon atoms of the alkoxy group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 19 carbon atoms, such as methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group and the like. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 20 carbon atoms, such as acetyl group, propionyl group and butyryl group and the like. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 19 carbon atoms, such as acetyloxy group, propionyloxy group, butyryloxy group and the like. Examples of the alkoxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 18 carbon atoms, such as butoxycarbonyloxy group and the like. The number of carbon atoms of the alkoxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkoxycarbonyloxy group is preferably 2 to 10, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkylthio group include alkylthio groups having 1 to 19 carbon atoms, such as methylthio group, ethylthio group, propylthio group, butylthio group, pentylthio group, hexylthio group, octylthio group, 2-ethylhexylthio group, nonylthio group, decylthio group, undecylthio group and the like. The number of carbon atoms of the alkylthio group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 19 carbon atoms, such as methylsulfonyl group, ethylsulfonyl group, propylsulfonyl group, butylsulfonyl group, pentylsulfonyl group, hexylsulfonyl group, octylsulfonyl group, 2-ethylhexylsulfonyl group, nonylsulfonyl group, decylsulfonyl group, undecylsulfonyl group and the like. The number of carbon atoms of the alkylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl-oxy group include alkanediyl-oxy groups having 1 to 19 carbon atoms, such as methylene-oxy group, ethylene-oxy group, propanediyl-oxy group, butanediyl-oxy group, pentanediyl-oxy group and the like. The number of carbon atoms of the alkanediyl-oxy group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl-oxycarbonyl group include alkanediyl-oxycarbonyl groups having 2 to 19 carbon atoms, such as a methylene-oxycarbonyl group, an ethylene-oxycarbonyl group, a propanediyl-oxycarbonyl group, and a butanediyl-oxycarbonyl group. Examples of the alkanediyl-carbonyl group include alkanediyl-carbonyl groups having 2 to 20 carbon atoms, such as a methylene-carbonyl group, an ethylene-carbonyl group, a propanediyl-carbonyl group, a butanediyl-carbonyl group, and a pentanediyl-carbonyl group. Examples of the alkanediyl-carbonyloxy group include alkanediyl-carbonyloxy groups having 2 to 19 carbon atoms, such as a methylene-carbonyloxy group, an ethylene-carbonyloxy group, a propanediyl-carbonyloxy group, and a butanediyl-carbonyloxy group. The number of carbon atoms of the alkanediyl-oxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkanediyl-carbonyl group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkanediyl-carbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkanediyl-sulfonyl group include alkanediyl-sulfonyl groups having 1 to 19 carbon atoms, such as a methylene-sulfonyl group, an ethylene-sulfonyl group, and a propylene-sulfonyl group. The number of carbon atoms of the alkanediyl-sulfonyl group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl-thio group include alkanediyl-thio groups having 1 to 19 carbon atoms, such as a methylene-thio group, an ethylene-thio group, and a propylene-thio group. The number of carbon atoms of the alkanediyl-thio group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the cycloalkoxy group include cycloalkoxy groups having 3 to 19 carbon atoms, such as a cyclohexyloxy group. Examples of the cycloalkylalkoxy group include cycloalkylalkoxy groups having 4 to 19 carbon atoms, such as a cyclohexylmethoxy group. Examples of the aromatic hydrocarbon group-carbonyloxy group include aromatic hydrocarbon group-carbonyloxy groups having 7 to 19 carbon atoms, such as a benzoyloxy group. Examples of the aromatic hydrocarbon group-carbonyl group include aromatic hydrocarbon group-carbonyl groups having 7 to 20 carbon atoms, such as a benzoyl group. Examples of the aromatic hydrocarbon group-oxy group include aromatic hydrocarbon group-oxy groups having 6 to 19 carbon atoms, such as a phenyloxy group.

[0024] Examples of the group in which -CH2- in the alicyclic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include the groups shown below. Also included are the groups shown below in which -O- is replaced by -S- and -CO- is replaced by -SO2-. The bonding site may be any position. TIFF2025091391000015.tif47169 Examples of groups in which -CH2- in a group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group is replaced with -O-, -S-, -CO- or -SO2- include the same groups as exemplified in this specification, within the upper limit of the number of carbon atoms permitted. A 1 , A 2 and A 3 The substituents that the hydrocarbon group may have include R 4 ~R 9 The substituents which the hydrocarbon group may have include the same groups as those exemplified above as the substituents which the hydrocarbon group may have.

[0025] A 1 , A 2 and A 3is, independently of each other, a single bond or a hydrocarbon group having 1 to 20 carbon atoms (the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. However, at least one of -CH2- contained in the hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2-).) is preferable. Specifically, A 1 is, ***-L 011 -X 01 -L 012 -, and A 2 is, ***-L 021 -X 02 -L 022 -, and A 3 is, ***-L 031 -X 03 -L 032 -(where X 01 , X 02 and X 03 each independently represent -O-, -CO-, -S- or -SO2-. L 011 , L 012 , L 021 , L 022 , L 031 and L 032 each independently represent a single bond or a hydrocarbon group having 1 to 18 carbon atoms, the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. However, the total number of carbon atoms of L 011 and L 012 is 0 to 18, and the total number of carbon atoms of L 021 and L 022 is 0 to 18, and the total number of carbon atoms of L 031 and L 032 is 0 to 18. *** represents the bonding site with Ar 1 , Ar 2 or Ar 3 .) is more preferable, and A 1 is, ***-X 01 -L 01 - or ***-L 01 -X 01 -, and A 2 is, ***-X 02 -L02 - or *** - L 02 - X 02 - is, A 3 is, *** - X 03 - L 03 - or *** - L 03 - X 03 - is (X 01 , X 02 and X 03 each independently represents -O-, -CO-, -S- or -SO2-. L 01 , L 02 and L 03 each independently represents a single bond or a hydrocarbon group having 1 to 18 carbon atoms, the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. *** is Ar 1 , Ar 2 or Ar 3 represents the bonding site with. ) It is more preferable. A 1 , A 2 and A 3 are preferably those having no substituent other than replacement with -O-, -CO-, -S- or -SO2. L 011 , L 012 , L 021 , L 022 , L 031 , L 032 , L 01 , L 02 and L 03 The hydrocarbon group having 1 to 18 carbon atoms (the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2.) includes groups similar to the groups mentioned for A 1 , A 2 and A 3 are mentioned. X 01 , X 02 and X 03 each independently is preferably -O- or -S-, and more preferably -O-. L 011 , L 012 , L021 , L 022 , L 031 , L 032 , L 01 , L 02 and L 03 are each independently preferably a single bond or a hydrocarbon group having 1 to 18 carbon atoms (wherein -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), more preferably a single bond or a hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), still more preferably a single bond, a chain hydrocarbon group having 1 to 9 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms or a group combining a chain hydrocarbon group having 1 to 4 carbon atoms and an alicyclic hydrocarbon group having 3 to 10 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group and the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), even more preferably a single bond or an alkanediyl group having 1 to 6 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), yet even more preferably a single bond or an alkanediyl group having 1 to 4 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), and still even more preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-). Among them, a single bond, a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-2,2-diyl group, a carbonyl group, a carbonyloxy group, a carbonyloxymethylene group, an ethyleneoxy group, an ethyleneoxymethylene group, a methylenecarbonyloxy group, a methylenecarbonyloxymethylene group or an ethyleneoxycarbonyl group is preferable, and a single bond, a methylene group, an ethane-1,1-diyl group, a propane-1,1-diyl group, a propane-2,2-diyl group or a carbonyl group is more preferable. However, L 011 and L 012 have a total carbon number of 0 to 18, and L 021 and L 022The total number of carbon atoms with [substance not specified] is from 0 to 18, and L 031 and L 032 The total number of carbon atoms with [substance not specified] is from 0 to 18.

[0026] m1 is preferably 0, 1, 2, 3 or 4, more preferably 0, 1, 2 or 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1. m2 is preferably 0, 1, 2, 3 or 4, more preferably 0, 1, 2 or 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1. m3 is preferably 0, 1, 2, 3 or 4, more preferably 0, 1, 2 or 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1. m4 is preferably 0, 1, 2 or 4, and more preferably 0, 1 or 2. m5 is preferably 0, 1, 2 or 4, and more preferably 0, 1 or 2. m6 is preferably 0, 1, 2 or 4, and more preferably 0, 1 or 2. m7 is preferably 0, 1, 2, 3 or 4, more preferably 0, 1, 2 or 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1. m8 is preferably 0, 1, 2, 3 or 4, more preferably 0, 1, 2 or 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1. m9 is preferably 0, 1, 2, 3 or 4, more preferably 0, 1, 2 or 3, even more preferably 0, 1 or 2, and even more preferably 0 or 1.

[0027] R 1 、R 2 and R 3 of Ar 1 、Ar 2 and Ar 3 The bonding positions to [substances not specified] are at Ar1 、 Ar 2 and Ar 3 are groups derived from benzene rings, each independently, A 1 、 A 2 and A 3 can be at the ortho, meta, or para position with respect to the bonding position of. Among them, A 1 、 A 2 and A 3 are preferably bonded to the para or meta position with respect to the bonding position, and more preferably bonded to the para position. Also, when Ar 1 、 Ar 2 and Ar 3 are groups derived from naphthalene rings, for example, when the bonding positions of A 1 、 A 2 and A 3 are at the 1-position, it can be at any of the 2nd to 8th positions, and when the bonding positions of A 1 、 A 2 and A 3 are at the 2-position, it can be at any of the 1st and 3rd to 8th positions. Among them, when the bonding positions of A 1 、 A 2 and A 3 are at the 1-position, it is preferably bonded to the 3rd to 6th positions, and when the bonding positions of A 1 、 A 2 and A 3 are at the 2-position, it is preferably bonded to the 4th to 7th positions. R 4 、 R 5 and R 6 's bonding positions to Ar 1 、 Ar 2 and Ar 3 are not particularly limited, but when Ar 1 、 Ar 2 and Ar 3 are groups derived from benzene rings, the bonding positions of R 4 、 R 5 and R 6 to Ar 1 、 Ar 2 and Ar 3 are each independently, A 1 、 A 2 and A 3Regarding the bonding position of , it may be any of the ortho, meta, or para positions. Among them, when m4, m5, and m6 are 1, R 4 , R 5 and R 6 are each independently preferably bonded to the para or meta position with respect to the bonding position of A 1 , A 2 and A 3 , and more preferably bonded to the meta position. When m4, m5, and m6 are 2, R 4 , R 5 and R 6 are each independently preferably such that one is bonded to the ortho or meta position and one is bonded to the para or meta position with respect to the bonding position of A 1 , A 2 and A 3 , and more preferably two are bonded to the meta position. When m4, m5, and m6 are 3, R 4 , R 5 and R 6 are each independently preferably such that two are bonded to the ortho or meta position and one is bonded to the para or meta position with respect to the bonding position of A 1 , A 2 and A 3 , and more preferably one is bonded to the ortho position and two are bonded to the meta position. When m4, m5, and m6 are 4, R 4 , R 5 and R 6 are each independently preferably such that two are bonded to the ortho or meta position and two are bonded to the para or meta position with respect to the bonding position of A 1 , A 2 and A 3 , and more preferably two are bonded to the ortho position and two are bonded to the meta position. Also, when Ar 1 , Ar 2 and Ar 3 are groups derived from a naphthalene ring, for example, when the bonding positions of A 1 , A 2 and A 3 are at the 1-position, it may be any of the 2nd to 8th positions, and A 1 , A 2 and A 3When the bonding position is the 2nd position, it may be any of the 1st position and the 3rd to 8th positions. Among them, A 1 A 2 and A 3 When the bonding position is the 1st position, it is preferable that at least one is bonded to the 3rd to 6th positions, A 1 A 2 and A 3 When the bonding position is the 2nd position, it is preferable that at least one is bonded to the 4th to 7th positions. R 7 R 8 and R 9 The bonding positions of the benzene rings of + can each independently be any of the ortho, meta, and para positions with respect to the bonding position of 7 R 8 R 9 and R 7 R 8 and R 9 When + are linear alkyl groups having 2 to 12 carbon atoms, each independently, the bonding positions of the benzene rings of + can be any of the ortho, meta, and para positions with respect to the bonding position of Among them, when m7, m8, and m9 are 1, 7 R 8 R 9 and R + are each preferably bonded to the para or meta position with respect to the bonding position of 7 R 8 R 9 and R + are each preferably bonded to the para or meta position with respect to the bonding position of 7 R 8 R 9 and R +With respect to the bonding position of [[ID=]], it is preferable that two are bonded at the ortho or meta position and one is bonded at the para or meta position, and it is more preferable that two are bonded at the meta position and one is bonded at the para position. When m7, m8, and m9 are 4, R 7 , R 8 and R 9 are each independently, with respect to the bonding position of X + , it is preferable that two are bonded at the ortho or meta position and two are bonded at the para or meta position, and it is more preferable that two are bonded at the meta position, one is bonded at the ortho position, and one is bonded at the para position.

[0028] A 1 , A 2 and A 3 The bonding positions of X + to the benzene ring to which they are bonded are each independently any of the ortho, meta, and para positions with respect to the bonding position of X + . Among them, it is preferable that they are bonded at the para or meta position with respect to the bonding position of X + . More specifically, when m1, m2, and m3 are 1, A 1 , A 2 and A 3 are each independently preferably bonded at the para or meta position with respect to the bonding position of X + , and more preferably bonded at the para position. When m1, m2, and m3 are 2, A 1 , A 2 and A 3 are each independently preferably bonded at one of the ortho or meta positions and one of the ortho or meta positions with respect to the bonding position of X + , and more preferably two are bonded at the meta position. When m1, m2, and m3 are 3, A 1 , A 2 and A 3 are each independently preferably bonded at two of the ortho or meta positions and one of the para or meta positions with respect to the bonding position of X + , and more preferably two are bonded at the meta position and one is bonded at the para position. When m1, m2, and m3 are 4, A 1 , A 2 and A3 is, independently of each other, X + is preferably bonded to the bonding position of X at the ortho or meta position, two are bonded to the para or meta position, more preferably two are bonded to the ortho position and two are bonded to the meta position.

[0029] Also, when X is a sulfur atom and m10 = 1, R 7 and R 8 or R 8 and R 9 may combine to form a ring containing S + . Among them, it is preferable that R 8 and R 9 combine to form a ring containing S + , and it is more preferably a cation represented by formula (I-C’). TIFF2025091391000016.tif51153[In formula (I-C’), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , m1, m2, m3, m4, m5, m6, m7, m8, m9, A 1 , A 2 , A 3 , Ar 1 , Ar 2 , Ar 3 have the same meanings as described above. X 7 represents a single bond, -CH2-, -O-, -S-, -CO-, -SO- or -SO2-.] X 7 is preferably a single bond, -CH2- or -O-.

[0030] Examples of the cation (I) represented by formula (I-C) include cations represented by formula (I-C-1) or formula (I-C-2) (hereinafter sometimes referred to as "cation (I-C-1)" and "cation (I-C-2)", respectively). Examples of the cation represented by formula (I-C') include the cation represented by formula (I-C'-1) (hereinafter sometimes referred to as "cation (I-C'-1)"). TIFF2025091391000017.tif136165[In formula (I-C-1), formula (I-C-2) and formula (I-C'-1), R 1 、R 2 、R 3 、R 4 、R 5 、R 6 、R 7 、R 8 、R 9 、m1, m2, m3, m4, m5, m6, m7, m8, m9, L 01 、L 02 、L 03 、X 01 、X 02 、X 03 and X 7 have the same meanings as described above.] X 01 、X 02 and X 03 are bonded to the benzene ring at positions that are the same as the positions at which they are bonded to the benzene rings of A 1 、A 2 and A 3 to the benzene ring, respectively.

[0031] Examples of the cation of salt (I) include cations represented by the following formula (I-c-1) to formula (I-c-70). TIFF2025091391000018.tif240154

[0032] TIFF2025091391000019.tif251161

[0033] TIFF2025091391000020.tif251166

[0034] TIFF2025091391000021.tif254165

[0035] TIFF2025091391000022.tif122150

[0036] 〔Anion (I)〕 AI - Examples of the organic anion represented by [ ] include sulfonate anions, sulfonylimide anions, and sulfonylmethide anions. Examples of the sulfonate anion include anions represented by formula (I-A) (hereinafter sometimes referred to as "anion (I-AA)"). TIFF2025091391000023.tif1386[In formula (I-A), all symbols have the same meanings as described above.]

[0037] In formula (I-A), L b1 Examples of the (nb1 + 1)-valent hydrocarbon group of [ ] include a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, a monovalent aromatic hydrocarbon group, and a monovalent group formed by combining two or more of these groups, from which nb1 hydrogen atoms are removed, and a group that binds to one or more L b2 and binds to [ ]. The number of carbon atoms of the hydrocarbon group is preferably 1 to 48, more preferably 1 to 42, even more preferably 1 to 36, still more preferably 1 to 30, and even still more preferably 1 to 24. Examples of the chain hydrocarbon group include a group obtained by removing nb1 hydrogen atoms from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specific examples include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, sec-butyl group, iso-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, heptadecyl group, and the like. Examples of the alkenyl group include ethenyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, tert-butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, isooctenyl group, and nonenyl group. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 36, more preferably 1 to 24, still more preferably 1 to 20, even more preferably 1 to 18, still even more preferably 1 to 12, and even more preferably 1 to 10. Examples of the alicyclic hydrocarbon group include a group obtained by removing nb1 hydrogen atoms from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, and the like. Examples of the polycyclic cycloalkyl group include a cycloalkyl group having a crosslinked structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are spiro-bonded. Examples of the cycloalkyl group having a crosslinked structure include norbornyl group, adamantyl group, and the like. Examples of the cycloalkyl group in which two or more rings are condensed include bicyclo[4,4,0]decane group, steroid group (steroid skeleton), and the like. Examples of the cycloalkyl group in which two rings are spiro-bonded include a spirocyclic cycloalkyl group in which one cycloalkyl group selected from the group consisting of cyclopentyl group, cyclohexyl group, norbornyl group, and adamantyl group and a cycloalkyl group having 5 to 8 carbon atoms are spiro-bonded. In addition, a double bond may be formed between two carbon atoms included in the alicyclic hydrocarbon group. More specifically, examples of the alicyclic hydrocarbon group include those represented by the following formula. TIFF2025091391000024.tif26168 When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 24, more preferably 3 to 20, still more preferably 3 to 18, even more preferably 3 to 12, even still more preferably 3 to 10, and even yet more preferably 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 6 to 24, more preferably 6 to 20, still more preferably 6 to 18, even more preferably 6 to 12, and even still more preferably 7 to 12. Examples of the aromatic hydrocarbon group include a group obtained by removing nb1 hydrogen atoms from an aryl group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a fluorenyl group, and the like. More specifically, examples of the aromatic hydrocarbon group include those represented by the following formula. TIFF2025091391000025.tif1085 The number of carbon atoms in the aromatic hydrocarbon group is preferably 4 to 24, more preferably 4 to 20, still more preferably 4 to 18, even more preferably 5 to 14, even still more preferably 5 to 10, and even yet more preferably 6 to 10. L b1Among the hydrocarbon groups, examples of the group in which -CH2- contained in the chain hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include a hydroxy group (a group in which -CH2- contained in the methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in the ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- contained in the methylene group is replaced by -CO-), an oxy group (a group in which -CH2- contained in the methylene group is replaced by -O-), an alkoxy group (a group in which -CH2- at any position contained in the alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -O-CO-), an alkylthio group (a group in which -CH2- at any position contained in the alkyl group is replaced by -S-), an alkylcarbonyl group (a group in which -CH2- at any position contained in the alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkyl group is replaced by -CO-O-), an alkylsulfonyl group (a group in which -CH2- at any position contained in the alkyl group is replaced by -SO2-), an alkanedioxy group (a group in which -CH2- at any position contained in the alkanedioyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in the alkanedioyl group is replaced by -O-CO-), an alkanedioylcarbonyl group (a group in which -CH2- at any position contained in the alkanedioyl group is replaced by -CO-), an alkanedioylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in the alkanedioyl group is replaced by -CO-O-), an alkanediylthio group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -S-), an alkanediylsulfonyl group (a group in which -CH2- at any position contained in the alkanediyl group is replaced by -SO2-), and the like. These replaced groups include those similar to the groups exemplified in this specification within the range allowed by the upper limit of the number of carbon atoms. L b1Among the hydrocarbon groups, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -CO-, -S- or -SO2- include groups containing structures such as cyclic ethers, cyclic ketones, cyclic esters (lactones), cyclic thioethers, cyclic acetals, cyclic sulfonic acid esters (sultones), and the like. Specifically, alicyclic hydrocarbon groups represented by the following formulas can be mentioned. The bonding position of the alicyclic hydrocarbon group listed in the following formulas can be any position. TIFF2025091391000026.tif48165L b1 Among the hydrocarbon groups, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-. Examples of the group in which -CH2- is replaced by -O- or -S- include groups derived from a furan ring or a thiophene ring, respectively. Specifically, aromatic hydrocarbon groups represented by the following formulas can be mentioned. TIFF2025091391000027.tif1324L b1 Among the hydrocarbon groups, examples of the group in which -CH2- contained in the group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. Examples of the group combining two or more of a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group include a group combining the above chain hydrocarbon group and the above alicyclic hydrocarbon group, a group combining the above chain hydrocarbon group and the above aromatic hydrocarbon group, a group combining the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group, and a group combining the above chain hydrocarbon group, the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group. The group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group may be a condensed ring. L b2 Examples of the divalent hydrocarbon group include a divalent chain hydrocarbon group, a divalent alicyclic hydrocarbon group, a divalent aromatic hydrocarbon group, and a group combining two or more of these groups, and a group obtained by removing one hydrogen atom from a monovalent hydrocarbon group and bonding to Y b1 and the like. L b2The divalent chain hydrocarbon group, divalent alicyclic hydrocarbon group, divalent aromatic hydrocarbon group, and divalent group formed by combining two or more of these groups, within the range permitted by the upper limit of the number of carbon atoms, are each L b1 Examples include groups obtained by removing one hydrogen atom from the monovalent chain hydrocarbon group, monovalent alicyclic hydrocarbon group, monovalent aromatic hydrocarbon group, and monovalent group formed by combining two or more of these, exemplified by b1 . L b1 and L b2 Examples of the substituent that the hydrocarbon group of L and L may have include a halogen atom, a cyano group, a nitro group, etc. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. L b1 and L b2 When L and L are groups combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a chain hydrocarbon group, substantially, the chain hydrocarbon group may be regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. Also, when -CH2- of the chain hydrocarbon group contained in the hydrocarbon group of L and L is replaced by -O-, -CO-, -S-, or -SO2-, the hydrocarbon group of L and L can substantially have substituents such as a hydroxy group, a carboxy group, a carbonyl group, an oxycarbonyl group, a carbonyloxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, an alkylthio group, an alkylsulfonyl group, etc. b1 and L b2 The number of substituents that L and L may have is not particularly limited, and they may have a plurality of substituents. b1 and L b2 Examples of the cyclic hydrocarbon group of Y include an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group. L b1 and L b2 The alicyclic hydrocarbon group and the aromatic hydrocarbon group of Y are each L Y b1 Examples of the cyclic hydrocarbon group of Y include an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group. Y b1 The alicyclic hydrocarbon group and the aromatic hydrocarbon group of Y are each L b1Examples thereof include the same as the alicyclic hydrocarbon group and aromatic hydrocarbon group exemplified above, and when having no substituent, it may be a monovalent alicyclic hydrocarbon group or aromatic hydrocarbon group. Y b1 Examples of the substituent that the methyl group of b1 may have include a halogen atom, a cyano group, a hydroxy group, a nitro group, and the like. Y b1 Examples of the substituent that the cyclic hydrocarbon group of b1 may have include a halogen atom, a cyano group, a nitro group, or a hydrocarbon group having 1 to 18 carbon atoms which may have a halogen atom, a cyano group or a nitro group (in the hydrocarbon group, -CH2- contained therein may be replaced by -O-, -S-, -CO- or -SO2-). Y b1 The number of carbon atoms of the hydrocarbon group that the cyclic hydrocarbon group of b1 may have is not included in the number of carbon atoms of the cyclic hydrocarbon group of b1 . b1 The number of carbon atoms of the cyclic hydrocarbon group of b1 is not included. Examples of the halogen atom include the same halogen atoms as those exemplified as the substituent of b1 and b2 . b1 and b2 b2 Examples of the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of b1 may have as a substituent include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining these groups. Examples of the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group combining two or more of these groups include, within the range allowed by the upper limit of the number of carbon atoms, the same groups as those exemplified for the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group combining two or more of these groups in b1 . Further, examples of the group in which -CH2- contained in the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of b1 may have as a substituent is replaced by -O-, -S-, -CO- or -SO2- include, within the range allowed by the upper limit of the number of carbon atoms, the same groups as those exemplified for the group in which -CH2- contained in the hydrocarbon group of b1 is replaced by -O-, -S-, -CO- or -SO2-. Y b1 Examples of the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of b1 may have as a substituent include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group combining these groups. Examples of the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group combining two or more of these groups include, within the range allowed by the upper limit of the number of carbon atoms, the same groups as those exemplified for the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group combining two or more of these groups in b1 . Further, examples of the group in which -CH2- contained in the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of b1 may have as a substituent is replaced by -O-, -S-, -CO- or -SO2- include, within the range allowed by the upper limit of the number of carbon atoms, the same groups as those exemplified for the group in which -CH2- contained in the hydrocarbon group of b1 is replaced by -O-, -S-, -CO- or -SO2-. b1 Examples of the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group combining two or more of these groups include, within the range allowed by the upper limit of the number of carbon atoms, the same groups as those exemplified for the chain hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group combining two or more of these groups in b1 . b1 Examples of the group in which -CH2- contained in the hydrocarbon group having 1 to 18 carbon atoms that the cyclic hydrocarbon group of b1 may have as a substituent is replaced by -O-, -S-, -CO- or -SO2- include, within the range allowed by the upper limit of the number of carbon atoms, the same groups as those exemplified for the group in which -CH2- contained in the hydrocarbon group of b1 is replaced by -O-, -S-, -CO- or -SO2-. b1 Examples of the group in which -CH2- contained in the hydrocarbon group of b1 is replaced by -O-, -S-, -CO- or -SO2- include, within the range allowed by the upper limit of the number of carbon atoms, the same groups as those exemplified for the group in which -CH2- contained in the hydrocarbon group of b1 is replaced by -O-, -S-, -CO- or -SO2-. b1The hydrocarbon group having 1 to 18 carbon atoms which may have an annular hydrocarbon group as a substituent may constitute a protecting group or a leaving group (an acid-labile group or a base-labile group) generally used in the art.

[0038] The anion represented by the formula (I-A) is preferably an anion represented by the following formula (I-A1) (hereinafter sometimes referred to as "anion (I-A1)") or an anion represented by the formula (I-A2) (hereinafter sometimes referred to as "anion (I-A2)"). TIFF2025091391000028.tif28126[In the formula (I-A1), L b2 and Y b1 have the same meaning as in the formula (I-A). Q b1 Q b2 Q b3 and Q b4 each independently represents a hydrogen atom, a fluorine atom, a perfluoroalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. z1 represents any integer from 0 to 6. When z1 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. X 1 represents -O-CO-, -CO-O-, -O-CO-O- or -O-. L b3 represents a single bond or an (nb2 + 1)-valent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. nb2 represents any integer from 1 to 3. When nb2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other.] Q b1 Q b2 Q b3 and Q b4 Examples of the alkyl group of include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group. Q b1 Qb2 , Q b3 and Q b4 Examples of the perfluoroalkyl group of Q and Q include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group, a perfluorohexyl group, and the like. Q b1 and Q b2 is Q b1 and Q b2 It is preferable that at least one of Q and Q contains a fluorine atom or a perfluoroalkyl group, more preferably a fluorine atom or a perfluoroalkyl group, still more preferably a fluorine atom or a trifluoromethyl group, and even more preferably both are fluorine atoms. Q b3 and Q b4 are each independently preferably a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 3 carbon atoms. Q b3 is preferably a hydrogen atom, a fluorine atom, or a perfluoroalkyl group having 1 to 3 carbon atoms. Q b4 is preferably a hydrogen atom or a fluorine atom. z1 is preferably any integer from 0 to 3, and more preferably 0, 1, or 2. X 1 is preferably -O-CO- or -CO-O-.

[0039] L b3 Examples of the hydrocarbon group in L include the same hydrocarbon groups as the examples of L in formula (I-A) within the range allowed by the upper limit of the number of carbon atoms. b1 In formula (I-A1), L b3 ​is a single bond, an optionally substituted chain hydrocarbon group having 1 to 12 carbon atoms (in the chain hydrocarbon group, -CH2- may be replaced by -O- or -CO-), an optionally substituted alicyclic hydrocarbon group having 3 to 18 carbon atoms (in the alicyclic hydrocarbon group, -CH2- may be replaced by -O-, -S-, -CO- or -SO2-), an optionally substituted aromatic hydrocarbon group having 6 to 10 carbon atoms (in the aromatic hydrocarbon group, -CH2- may be replaced by -O- or -S-), or a group formed by combining two or more of these groups. It is preferably a single bond, a chain hydrocarbon group having 1 to 6 carbon atoms or a group represented by the following formula (Lb3-1). When -CH2- contained in the chain hydrocarbon group is replaced by -O- or -CO-, the number thereof is preferably 1 to 4. It is preferable that one -CH2-CH2- contained in the chain hydrocarbon group is replaced by -O-CO- or -CO-O-, or one -CH2-CH2-CH2- contained in the chain hydrocarbon group is replaced by -O-CO-O-. TIFF2025091391000029.tif1581[In formula (Lb3-1), nb2 represents the same meaning as in formula (I-A1). L b31 represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms. In the chain hydrocarbon group, -CH2- may be replaced by -O- or -CO-, and the chain hydrocarbon group may have a substituent. W b3 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms. In the alicyclic hydrocarbon group, -CH2- may be replaced by -O-, -S-, -CO- or -SO2-. In the aromatic hydrocarbon group, -CH2- may be replaced by -O- or -S-. The alicyclic hydrocarbon group and the aromatic hydrocarbon group may have a substituent. * and ** represent bonding sites. * represents the bonding site with X 1 and represents the bonding site with.] In formula (Lb3-1), L b31 's chain hydrocarbon group, as long as the upper limit of the number of carbon atoms permits, L b1Examples thereof include the same groups as the chain hydrocarbon groups exemplified above. In formula (Lb3-1), W b3 The alicyclic hydrocarbon group and the aromatic hydrocarbon group of, as long as the upper limit of the number of carbon atoms permits, are the same groups as the alicyclic hydrocarbon groups and the aromatic hydrocarbon groups exemplified by L b1 Examples thereof include the same groups as the alicyclic hydrocarbon groups and the aromatic hydrocarbon groups exemplified above. In formula (Lb3-1), L b31 The substituents that the chain hydrocarbon group of may have and W b3 The substituents that the alicyclic hydrocarbon group and the aromatic hydrocarbon group of may have are the same groups as the substituents exemplified as the substituents that the hydrocarbon group of L b1 Examples thereof include the same groups as the substituents exemplified above. L b31 Is preferably a single bond or an alkanediyl group having 1 to 6 carbon atoms (the -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-). Among them, as W b3 The alicyclic hydrocarbon group and the aromatic hydrocarbon group of are preferably the alicyclic hydrocarbon group and the aromatic hydrocarbon group represented below. In the alicyclic hydrocarbon group and the aromatic hydrocarbon group represented below, * and ** represent the bonding sites, * represents the bonding site with X 1 Or L b31 Represents the bonding site with, ** represents a hydrogen atom, a substituent or the bonding site with L b2 Represents the bonding site with, and at least one ** represents the bonding site with L b2 Represents the bonding site with. Further, in the alicyclic hydrocarbon group represented below, the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. When the -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2-, it is preferably a ether ring, an ester ring (lactone), a carbonate ester ring, a sulfonic acid ester ring ( sultone) or an acetal ring is formed. TIFF2025091391000030.tif37165 In formula (I-A1), L b2is a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), preferably a single bond, -O-, -O-CO-, -CO-O-, -O-CO-O- or *-L b21 -X 2 -L b22 -**(L b21 and L b22 either one of which represents a chain hydrocarbon group having 1 to 6 carbon atoms, and the other represents a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms. X 2 represents -O-, -CO-O-, -O-CO- or -O-CO-O-. * and ** represent bonding sites, and ** represents the bonding site with Y b1 However, L b21 X 2 and L b22 The total number of carbon atoms of is 12 or less.) is more preferable. In formula (I-A1), Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, and even more preferably an alicyclic hydrocarbon group having 3 to 16 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 10 carbon atoms which may have a substituent. Specifically, it is preferably a group represented by the following formula (Y1) to formula (Y36). In formula (Y1) to formula (Y36), R Yb represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms among the substituents that the cyclic hydrocarbon group of Y b1 may have, and R Yc represents a hydrogen atom or a substituent that the cyclic hydrocarbon group of Y b1 may have, and * represents L b2Represents a binding site to. The alicyclic hydrocarbon group and aromatic hydrocarbon group represented by the following formula are not particularly shown in the following formula, but other than Y b1 The cyclic hydrocarbon group of may also have a substituent that it may have. TIFF2025091391000031.tif84159

[0040] Examples of the anion represented by formula (I-A1) include anions represented by formula (I-A1-1) to formula (I-A1-85) [hereinafter, may be referred to as "anion (I-A1-1)" etc. according to the formula number.]. An anion represented by any of formula (I-A1-1) to formula (I-A1-4), formula (I-A1-9), formula (I-A1-10), formula (I-A1-24) to formula (I-A1-33), formula (I-A1-36) to formula (I-A1-40), and formula (I-A1-47) to formula (I-A1-85) is more preferable. TIFF2025091391000032.tif250164

[0041] TIFF2025091391000033.tif249154

[0042] TIFF2025091391000034.tif217164

[0043] Here, R i2 ~R i7 are, independently of each other, for example, an alkyl group having 1 to 4 carbon atoms, preferably a methyl group or an ethyl group. R i8 is, for example, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms, an alicyclic hydrocarbon group having 5 to 12 carbon atoms, or a group formed by combining these, more preferably a methyl group, an ethyl group, a cyclohexyl group, or an adamantyl group. L A41 is a single bond or an alkanediyl group having 1 to 4 carbon atoms. Q b1 and Q b2 represent the same meaning as described above. Specific examples of the anion represented by formula (I-A1) include the anions described in JP-A-2010-204646.

[0044] Examples of the anion represented by the preferable formula (I-A1) include anions represented by formula (I-a-1) to formula (I-a-70). TIFF2025091391000035.tif181163

[0045] TIFF2025091391000036.tif249161

[0046] TIFF2025091391000037.tif71167

[0047] Among them, an anion represented by any one of formula (I-a-1) to formula (I-a-4), formula (I-a-7) to formula (I-a-11), formula (I-a-14) to formula (I-a-30), and formula (I-a-35) to formula (I-a-70) is preferable.

[0048] The anion represented by formula (I-A2) is represented by the following formula. TIFF2025091391000038.tif2496[In formula (I-A2), L b2 and Y b1 have the same meaning as in formula (I-A). R b1 represents a halogen atom or an alkyl group having 1 to 6 carbon atoms, and -CH2- contained in the alkyl group may be replaced by -O- or -CO-. nb4 represents any integer from 1 to 5. When nb4 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. nb3 represents any integer from 0 to 4. When nb3 is 2 or more, the plurality of R b1 may be the same as or different from each other. However, 1 ≦ nb4 + nb3 ≦ 5 is satisfied.]

[0049] In formula (I-A2), the hydrocarbon group of L b2 and Y b1Examples of the cyclic hydrocarbon group include, within the range permitted by the upper limit of the number of carbon atoms, L in formula (I-A). b2 Examples of the hydrocarbon group and Y b1 are the same as those of the cyclic hydrocarbon group. L b2 Examples of the hydrocarbon group, Y b1 Examples of the methyl group and the substituent that the cyclic hydrocarbon group may have are also the same as those of L in formula (I-A). b2 Examples of the hydrocarbon group, Y b1 Examples of the methyl group and the substituent that the cyclic hydrocarbon group may have are the same as those of the methyl group and the substituent that the cyclic hydrocarbon group may have. These hydrocarbon groups, methyl group, and cyclic hydrocarbon group may have one or more substituents. L b2 is preferably a chain hydrocarbon group having 1 to 12 carbon atoms (wherein -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), more preferably *-CO-O-L b41 -(L b41 is a single bond or a chain hydrocarbon group having 1 to 6 carbon atoms, and -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-. * represents the bonding site with the benzene ring to which SO3 - is bonded. L b41 is preferably a single bond or a chain hydrocarbon group having 1 to 3 carbon atoms.). More preferably, it is *-CO-O-. Y b1 is preferably a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (wherein -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-), more preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (wherein -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-) or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. Y in formula (B1-A1) b1 or L b1It is more preferable that it is an alicyclic hydrocarbon group or an aromatic hydrocarbon group exemplified above. Specifically, it is preferably a group represented by the above-described formulas (Y1) to (Y36), and more preferably a group represented by the above-described formulas (Y1) to (Y19).

[0050] In formula (I-A2), nb4 is preferably any integer from 1 to 4, more preferably any integer from 1 to 3, still more preferably 1 or 2, and even more preferably 2. When nb4 is 1 or 2, -L b2 -Y b1 is preferably bonded at the m-position substitution of the benzene ring with respect to the bonding position of SO3 - in the following structure. TIFF2025091391000039.tif28107[In the above formula, L b2 , Y b1 , R b1 , and nb3 have the same meanings as in formula (I-A2).] In formula (I-A2), when nb4 is 2 or more, a plurality of L b2 and Y b1 are preferably the same group as each other.

[0051] R b1 Examples of the alkyl group having 1 to 6 carbon atoms for R include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, and hexyl group. The number of carbon atoms of the alkyl group is preferably 1 to 4, and more preferably 1 to 3. R b1 Examples of the halogen atom for R include fluorine atom, chlorine atom, bromine atom, and iodine atom. Examples of the group in which -CH2- contained in the alkyl group is replaced by -O- or -CO- include hydroxy group, carboxy group, alkoxy group, alkoxycarbonyl group, alkylcarbonyl group, alkylcarbonyloxy group, oxy group, and carbonyl group. These replaced groups include those similar to the groups exemplified in the present specification as long as the upper limit of the number of carbon atoms allows. R b1is each independently preferably a halogen atom or an alkyl group having 1 to 4 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), more preferably a fluorine atom, an iodine atom or an alkyl group having 1 to 3 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methoxy group or a methyl group. nb3 is preferably any integer from 0 to 3, more preferably any integer from 0 to 2. In one embodiment, nb3 is preferably 0. In another embodiment, nb3 is preferably 1 or 2. When nb3 is 1, R b1 is preferably a halogen atom, and R b1 is more preferably a fluorine atom or an iodine atom. When nb3 is 2, one of R b1 is preferably a halogen atom and the other is preferably a halogen atom or an alkyl group having 1 to 4 carbon atoms, and one of R b1 is more preferably a fluorine atom or an iodine atom and the other is more preferably a fluorine atom, an iodine atom or an alkyl group having 1 to 3 carbon atoms.

[0052] Examples of the anion represented by the formula (I-A2) include the following anions. Among them, the anions represented by the formulas (I-a2-1) to (I-a2-20) are preferred, and the anions represented by the formulas (I-a2-1) to (I-a2-11), (I-a2-16) to (I-a2-20) are more preferred. In the following anions, some of R b1 are omitted and may contain substituents not shown. TIFF2025091391000040.tif102154

[0053] In another embodiment, AI -The organic anion represented by may be a sulfonylimide anion or a sulfonylmethide anion. Examples of the sulfonylimide anion or the sulfonylmethide anion include an anion represented by the formula (I-B) (hereinafter sometimes referred to as "anion (I-B)").

[0054] The anion represented by the formula (I-B) is represented by the following formula. TIFF2025091391000041.tif1286[In the formula (I-B), A 1 represents a nitrogen atom or a carbon atom. L b2 ' represents a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a single bond or a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. Y b1 ' represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. nb5 represents an integer of 2 or 3. When nb5 is 2, A 1 is a nitrogen atom, and when nb5 is 3, A 1 is a carbon atom. The groups in a plurality of parentheses may be the same as or different from each other, and the groups in two parentheses may be bonded to form a ring containing A 1 .] In the formula (I-B), L b2 ' and Y b1 ' Examples of the hydrocarbon group, cyclic hydrocarbon group and substituent are the same groups as L b2 and Y b1 in the formula (I-A). In the formula (I-B), L b2 ' is a single bond, *-L b23 -, *-L b23 -X 2 - or *-L b23 -X 2 -W 2 -X 3 -(L b23represents an acyclic hydrocarbon group having 1 to 6 carbon atoms which may have a fluorine atom. X 2 and X 3 each independently represent -O-, -CO-O-, -O-CO-, -O-CO-O- or -O-. W 2 represents an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-. * represents the bonding site with SO2. ) is preferred. In formula (I-B), Y b1 ' is preferably a methyl group having a fluorine atom or a cyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent (the -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-). ), more preferably a trifluoromethyl group, an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. Specifically, it is preferably a trifluoromethyl group or a group represented by formula (Y1) to formula (Y36) exemplified in formula (I-A1). In formula (I-B), when two -SO2-L b2 '-Y b1 ' together form a ring containing A 1 , for example, an anion represented by formula (I-B') can be mentioned. TIFF2025091391000042.tif20116[In formula (I-B'), A 1 , Y b1’ , L b2’ and nb5 represent the same meanings as in formula (I-B). W b4 represents a disulfonylimide ring or a disulfonylmethide ring having 2 to 12 carbon atoms which may have a fluorine atom.] W b4The disulfonylimide ring or disulfonylmethide ring preferably has 3 to 12 carbon atoms, more preferably 3 to 6 carbon atoms, and the hydrogen atoms of the methylene groups contained in the ring are preferably replaced by fluorine atoms.

[0055] Examples of the anion represented by formula (I-B) include the following. Among them, the anions represented by formula (I-a3-1), formula (I-a3-2), formula (I-a3-12), and formula (I-a3-13) are preferred. TIFF2025091391000043.tif189164

[0056] Specific examples of salt (I) include salts obtained by arbitrarily combining the above-mentioned cations and anions. Specific examples of salt (I) are shown in the following table. In the following table, each symbol represents the symbol attached to the structure representing the above-mentioned anion or cation, and "~" indicates that each of salt (I) and anion (I) or cation (I) corresponds. For example, salt (I-1) is a salt composed of the anion represented by formula (I-a-1) and the cation represented by formula (I-c-1), salt (I-2) is a salt composed of the anion represented by formula (I-a-2) and the cation represented by formula (I-c-1), and salt (I-71) is a salt composed of the anion represented by formula (I-a-1) and the cation represented by formula (I-c-2). TIFF2025091391000044.tif3193 [Table 1] TIFF2025091391000046.tif244170 TIFF2025091391000047.tif244170 TIFF2025091391000048.tif244170 TIFF2025091391000049.tif218167

[0057] Among them, the salt (I) is preferably a salt obtained by combining an anion represented by any of the formulas (I-a-1) to (I-a-4), (I-a-7) to (I-a-11), (I-a-14) to (I-a-30), (I-a-35) to (I-a-70), (I-a2-1) to (I-a2-11), (I-a2-16) to (I-a2-20), (I-a3-1), (I-a3-2), (I-a3-12) and (I-a3-13) with a cation represented by any of the formulas (I-c-1) to (I-c-70).

[0058] <Acid generator> The acid generator of the present invention contains the salt (I). The acid generator of the present invention may contain one kind of the salt (I) or may contain two or more kinds of the salt (I). In the resist composition of the present invention, the total content rate of the salt (I) is preferably 1% by mass or more and 95% by mass or less, more preferably 2% by mass or more and 90% by mass or less, still more preferably 3% by mole or more and 80% by mole or less, even more preferably 4% by mole or more and 50% by mole or less, and still even more preferably 5% by mole or more and 40% by mole or less, based on the solid content of the resist composition. In addition to the salt (I), the acid generator of the present invention may contain a known acid generator (hereinafter sometimes referred to as "acid generator (B)") that acts as an acid generator in the resist field. However, it does not contain the salt (I). The acid generator (B) may be used alone or in combination of two or more.

[0059] The acid generator (B) may be either a nonionic compound or an ionic compound. Examples of the nonionic compound include sulfonate esters (e.g., 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, sulfonyloxy ketone, diazonaphthoquinone 4-sulfonate), sulfones (e.g., disulfone, ketosulfone, sulfonyldiazomethane), and the like. Examples of the ionic compound include onium salts containing an onium cation (e.g., diazonium salt, phosphonium salt, sulfonium salt, iodonium salt), and the like. Examples of the anion of the onium salt include sulfonic acid anion, sulfonylimide anion, sulfonylmethide anion, carboxylic acid anion, and the like. The acid generator (B) may be a part of the structural unit of the resin contained in the resist composition of the present invention, such as the structural unit (a7) described later.

[0060] As the acid generator (B), compounds that generate an acid by radiation described in, for example, JP-A-63-26653, JP-A-55-164824, JP-A-62-69263, JP-A-63-146038, JP-A-63-163452, JP-A-62-153853, JP-A-63-146029, U.S. Patent No. 3,779,778, U.S. Patent No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712, etc. can be used. Further, compounds produced by known methods may also be used. The acid generator (B) may be an acid generator having an acid-labile group. For example, the compound or resin serving as the acid generator may contain a partial structure serving as an acid-labile group, and the acid-labile group preferably contains the above-described group (1) or group (2).

[0061] A preferred form of the acid generator (B) is an organic cation Z1 + and a salt composed of an anion represented by formula (I-A), an anion represented by formula (I-A1), an anion represented by formula (I-A2), an anion represented by formula (I-B), and an anion selected from carboxylic acid anions (hereinafter sometimes referred to as "acid generator (B1)"). Examples of the carboxylic acid anion include the following. TIFF2025091391000050.tif41155

[0062] ZI + Examples of the organic cation of + include organic onium cations, organic sulfonium cations, organic iodonium cations, organic ammonium cations, benzothiazolium cations, and organic phosphonium cations. Among these, organic sulfonium cations and organic iodonium cations are preferred, and arylsulfonium cations or aryliodonium cations are more preferred. Specifically, cations represented by any of formula (b2-1) to formula (b2-5) (hereinafter, may be referred to as "cation (b2-1)" etc. according to the formula number) are included. However, ZI + The organic cation of + excludes the cation represented by formula (I-C). TIFF2025091391000051.tif84161[In formula (b2-1) to formula (b2-5), R b4 ~R b6 each independently represents a linear hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the hydrogen atom contained in the linear hydrocarbon group may be substituted with a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, or a glycidyloxy group, and the hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. R b4 and R b5 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH2- contained in the ring may be replaced with -O-, -S-, or -CO-. R b7 and Rb8 Each independently represents a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. m2 and n2 each independently represent any integer from 0 to 5. When m2 is 2 or more, a plurality of R b7 may be the same or different, and when n2 is 2 or more, a plurality of R b8 may be the same or different. R b9 and R b10 each independently represent a chain hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms. R b9 and R b10 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded, and -CH2- contained in the ring may be replaced by -O-, -S-, or -CO-. R b11 represents a hydrogen atom, a chain hydrocarbon group having 1 to 36 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. R b12 represents a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the chain hydrocarbon group may be substituted with an aromatic hydrocarbon group having 6 to 18 carbon atoms, and a hydrogen atom contained in the aromatic hydrocarbon group may be substituted with an alkoxy group having 1 to 12 carbon atoms or an alkylcarbonyloxy group having 1 to 12 carbon atoms. R b11 and R b12 may be bonded to each other to form a ring including -CH-CO- to which they are bonded, and -CH2- contained in the ring may be replaced by -O-, -S-, or -CO-. R b13 ~R b18 and R b21 ~R b26 each independently represent a halogen atom, a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, a fluorinated alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. R b13 and R b14 and R b21 and R b22 and R may be combined with each other to form a ring containing a sulfur atom together with the benzene ring to which they are attached, and the -CH2- contained in the ring may be replaced by -O-, -S- or -CO-. R b27 ~R b29 each independently represents a hydrogen atom or a group containing an acid-labile group. L b31 L b41 ~L b43 each independently represents a sulfur atom or an oxygen atom. o2, p2, s2, and t2 each independently represent an integer from 0 to 5. q2 and r2 each independently represent an integer from 0 to 4. u2 represents 0 or 1. o21, p22, q23, r24, t25 and s26 each independently represent an integer from 0 to 4. u3 represents an integer from 1 to 3 and satisfies 1 ≦ u3 + q23 ≦ 5. u4 and u5 each independently represent an integer from 0 to 3 and satisfy 0 ≦ u4 + o21 ≦ 5 and 0 ≦ u5 + p22 ≦ 5. When o2 is 2 or more, the plurality of Rs b13 are the same or different, when p2 is 2 or more, the plurality of Rs b14 are the same or different, when q2 is 2 or more, the plurality of Rs b15 are the same or different, when r2 is 2 or more, the plurality of Rs b16 are the same or different, when s2 is 2 or more, the plurality of Rs b17 are the same or different, when t2 is 2 or more, the plurality of Rs b18 are the same or different. When o21, p22, q23, r24, t25 and s26 are each 2 or more, the plurality of Rs b21 ~R b26 are each the same or different. When u3, u4 and u5 are each 2 or more, the groups within the plurality of parentheses are each the same or different.] When u2 is 0, at least one of o2, p2, q2, and r2 is 1 or more, and R b13 ~R b16 It is preferable that at least one of them is a halogen atom. When u2 is 1, at least one of o2, p2, s2, t2, q2, and r2 is 1 or more, and R b13 ~R b18 It is preferable that at least one of them is a halogen atom. Furthermore, when u2 is 0, r2 is preferably 1 or more, and more preferably 1. Also, when u2 is 0 and r2 is 1 or more, R b16 is preferably a halogen atom. The aliphatic hydrocarbon group represents a chain hydrocarbon group and an alicyclic hydrocarbon group. Examples of the chain hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group, and 2-ethylhexyl group. In particular, the chain hydrocarbon group of R b9 ~R b12 is preferably having 1 to 12 carbon atoms. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, and cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group, and the following groups. TIFF2025091391000052.tif10158 In particular, the alicyclic hydrocarbon group of R b9 ~R b12 is preferably having 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms. Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group include a methylcyclohexyl group, a dimethylcyclohexyl group, a 2-methyladamantan-2-yl group, a 2-ethyladamantan-2-yl group, a 2-isopropyladamantan-2-yl group, a methylnorbornil group, an isobornyl group, and the like. In the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an aliphatic hydrocarbon group, the total number of carbon atoms of the alicyclic hydrocarbon group and the aliphatic hydrocarbon group is preferably 20 or less. The alkyl fluoride group represents an alkyl group having 1 to 12 carbon atoms and having a fluorine atom, and examples thereof include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, and a perfluorobutyl group. The number of carbon atoms of the alkyl fluoride group is preferably 1 to 9, more preferably 1 to 6, and still more preferably 1 to 4.

[0063] Examples of the aromatic hydrocarbon group include aryl groups such as a phenyl group, a biphenyl group, a naphthyl group, and a phenanthryl group. The aromatic hydrocarbon group may have a chain hydrocarbon group or an alicyclic hydrocarbon group, and examples of the aromatic hydrocarbon group having a chain hydrocarbon group having 1 to 18 carbon atoms include a tolyl group, a xylyl group, a cumenyl group, a mesityl group, a p-ethylphenyl group, a p-tert-butylphenyl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group, and examples of the aromatic hydrocarbon group having an alicyclic hydrocarbon group having 3 to 18 carbon atoms include a p-cyclohexylphenyl group and a p-adamantylphenyl group. When the aromatic hydrocarbon group has a chain hydrocarbon group or an alicyclic hydrocarbon group, a chain hydrocarbon group having 1 to 18 carbon atoms and an alicyclic hydrocarbon group having 3 to 18 carbon atoms are preferred. Examples of the aromatic hydrocarbon group in which a hydrogen atom is substituted with an alkoxy group include a p-methoxyphenyl group. Examples of the chain hydrocarbon group in which a hydrogen atom is substituted with an aromatic hydrocarbon group include aralkyl groups such as a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, a dodecyloxy group, and the like. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, a butyryl group, and the like. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, a propylcarbonyloxy group, an isopropylcarbonyloxy group, a butylcarbonyloxy group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group, a 2-ethylhexylcarbonyloxy group, and the like. R b4 and R b5 The ring formed by R and R being bonded to each other together with the sulfur atom to which they are bonded may be any of a monocyclic, polycyclic, aromatic, non-aromatic, saturated, and unsaturated ring. Examples of this ring include rings having 3 to 18 carbon atoms, preferably rings having 4 to 18 carbon atoms. Further, examples of the ring containing a sulfur atom include 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings. For example, the following rings can be mentioned. * represents a bonding site. TIFF2025091391000053.tif23143R b9 and R b10 The ring formed by R and R together may be any of a monocyclic, polycyclic, aromatic, non-aromatic, saturated, and unsaturated ring. Examples of this ring include 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings. For example, a thiolan-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, a 1,4-oxathian-4-ium ring, and the like can be mentioned. R b11 and R b12The ring formed together with the group may be any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. Such rings include 3-membered to 12-membered rings, preferably 3-membered to 7-membered rings. Examples include oxocycloheptane ring, oxocyclohexane ring, oxonorbornane ring, oxoadamantane ring, etc. R b27 ~R b29 Examples of the group containing an acid-labile group of ~R c30 include -R c30 , -CO-O-R c10 or -L c30 -CO-O-R c10 wherein L c30 represents an alkanediyl group having 1 to 6 carbon atoms, and R R b27 ~R b29 The acid-labile group of may be a group represented by the following group (1) or group (2).

[0064] Among cations (b2-1) to (b2-5), preferably, cation (b2-1), cation (b2-4) or cation (b2-5). Examples of cation (b2-1) include the following cations. TIFF2025091391000054.tif158165 Examples of cation (b2-2) include the following cations. TIFF2025091391000055.tif18150 Examples of cation (b2-3) include the following cations. TIFF2025091391000056.tif26140 Examples of cation (b2-4) include the following cations. TIFF2025091391000057.tif122163 Examples of cation (b2-5) include the following cations. TIFF2025091391000058.tif115158

[0065] The salt (B1) is a combination of the above-mentioned anion and the above-mentioned organic cation, and these can be arbitrarily combined. As the salt (B1), preferably, it is any of the anions represented by any of Formula (I-a-1) to Formula (I-a-4), Formula (I-a-7) to Formula (I-a-11), Formula (I-a-14) to Formula (I-a-30), Formula (I-a-35) to Formula (I-a-70), Formula (I-a2-1) to Formula (I-a2-11), Formula (I-a2-16) to Formula (I-a2-20), Formula (I-a3-1) to Formula (I-a3-3), or Formula (I-3a-11) to Formula (I-3a-14), and a combination with cation (b2-1), cation (b2-2), cation (b2-3), cation (b2-4), or cation (b2-5).

[0066] As the acid generator (B), preferably, those represented by Formula (B1-1) to Formula (B1-105), Formula (B2-1) to Formula (B2-20), and Formula (B3-1) to Formula (B3-28) are exemplified. Among them, those containing an arylsulfonium cation are preferred, and those represented by Formula (B1-1) to Formula (B1-3), Formula (B1-5) to Formula (B1-7), Formula (B1-11) to Formula (B1-14), Formula (B1-20) to Formula (B1-26), Formula (B1-29), Formula (B1-31) to Formula (B1-105), Formula (B2-1) to Formula (B2-20), and Formula (B3-1) to Formula (B3-28) are particularly preferred. TIFF2025091391000059.tif176161

[0067] TIFF2025091391000060.tif254159

[0068] TIFF2025091391000061.tif254165

[0069] TIFF2025091391000062.tif254160

[0070] TIFF2025091391000063.tif249163

[0071] TIFF2025091391000064.tif250151

[0072] TIFF2025091391000065.tif187159

[0073] In another form of the acid generator (B), an anion in which the anion represented by the formula (B1) is replaced with a carboxylic acid anion is also preferably used as the acid generator (B). Examples of the carboxylic acid anion include the same ones as those described above.

[0074] When the resist composition of the present invention contains the salt (I) and the acid generator (B), the ratio of the content of the salt (I) to the content of the acid generator (B) (mass ratio; salt (I): acid generator (B)) is usually 1:99 to 99:1, preferably 2:98 to 98:2, more preferably 5:95 to 95:5, still more preferably 10:90 to 90:10, and particularly preferably 15:85 to 85:15. When the resist composition of the present invention contains the acid generator (B), the total content ratio of the salt (I) and the acid generator (B) is preferably 1% by mass or more and 95% by mass or less, more preferably 2% by mass or more and 90% by mass or less, still more preferably 3% by mole or more and 80% by mole or less, even more preferably 4% by mole or more and 50% by mole or less, and still even more preferably 5% by mole or more and 40% by mole or less, based on the solid content of the resist composition.

[0075] <Resin> The resin of the present invention is a resin (hereinafter sometimes referred to as "resin (A)") containing a structural unit represented by the formula (II) (hereinafter sometimes referred to as "structural unit (II)") and a structural unit having an acid-labile group (hereinafter sometimes referred to as "structural unit (a1)").

[0076] 〈Structural unit (II)〉 The structural unit (II) contained in the resin (A) is represented by the following formula (II). TIFF2025091391000066.tif2675[In formula (II), all symbols have the same meaning as described above.]

[0077] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include unsubstituted alkyl groups having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, and an n-hexyl group, and haloalkyl groups having 1 to 6 carbon atoms such as a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro-sec-butyl group, a perfluoro-tert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group. Preferred are unsubstituted alkyl groups having 1 to 4 carbon atoms, and more preferred are a methyl group and an ethyl group. R 12 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group.

[0078] L 2 and L 3 Examples of the divalent hydrocarbon group having 1 to 12 carbon atoms for L and L include divalent chain hydrocarbon groups such as alkanediyl groups, divalent alicyclic hydrocarbon groups, divalent aromatic hydrocarbon groups, or divalent groups formed by combining these. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, and hexane-1,6-diyl group; groups having a side chain of an alkyl group (especially an alkyl group having 1 to 4 carbon atoms (such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, etc.)) on the linear alkanediyl group; and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. The number of carbon atoms of the chain hydrocarbon group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, and even more preferably 1 to 3. Examples of the divalent alicyclic hydrocarbon group include monocyclic groups which are monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; and polycyclic groups which are polycyclic cycloalkanediyl groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, and adamantane-2,6-diyl group. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 10, more preferably 3 to 8. Examples of the divalent aromatic hydrocarbon group include phenylene group, naphthylene group, anthrylene group, p-methylphenylene group, p-tert-butylphenylene group, p-adamantylphenylene group, tolylene group, xylylene group, cumenylene group, mesitylene group, biphenylene group, phenanthrylene group, 2,6-diethylphenylene group, 2-methyl-6-ethylphenylene group, etc. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 10, more preferably 6. Examples of hydrocarbon groups combined with two or more types include groups formed by combining a chain hydrocarbon group with an alicyclic hydrocarbon group and / or an aromatic hydrocarbon group, such as -alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-alicyclic hydrocarbon group-, -alkanediyl group-alicyclic hydrocarbon group-alkanediyl group-, -alkanediyl group-aromatic hydrocarbon group-, -aromatic hydrocarbon group-alkanediyl group-, etc. In the case of a group formed by combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group with an alkanediyl group, the terminal of the alkanediyl group may be an alkyl group such as a methyl group. L 2 and L 3 are each independently preferably an alkanediyl group having 1 to 6 carbon atoms, more preferably an alkanediyl group having 1 to 3 carbon atoms, and even more preferably a methylene group or an ethylene group. L 11 is preferably a single bond or *-L 2 -CO-O-, more preferably a single bond or *-CH2-CO-O-, and even more preferably a single bond.

[0079] R 13 Examples of the alkyl group having 1 to 12 carbon atoms represented by include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, etc. The number of carbon atoms of the alkyl group is preferably 2 to 10, more preferably 2 to 8, even more preferably 3 to 8, and even more preferably 4 to 8. R 3 is preferably a linear alkyl group having 1 to 8 carbon atoms, more preferably a linear alkyl group having 2 to 8 carbon atoms, even more preferably a linear alkyl group having 3 to 8 carbon atoms, even more preferably a linear alkyl group having 4 to 8 carbon atoms, even more preferably an n-propyl group, an n-butyl group, an n-hexyl group or an n-octyl group, and even more preferably an n-butyl group, an n-hexyl group or an n-octyl group.

[0080] Specific examples of structural unit (II) include structural units represented by the following formulas (II-1) to (II-8), and structural units in which the methyl group corresponding to R 12 in the following formulas (II-1) to (II-8) is replaced by a hydrogen atom, and the like. Among them, the structural units represented by formula (II-1), formula (II-2), and formula (II-6) are preferable. TIFF2025091391000067.tif89149

[0081] Structural unit (II) is derived from a monomer represented by formula (II’) (hereinafter sometimes referred to as “monomer (II’)”). TIFF2025091391000068.tif2653[In formula (II’), all symbols have the same meanings as described above.]

[0082] Examples of monomer (II’) include monomers represented by the following formulas (II’-1) to (II’-8), and monomers in which the hydrogen atom corresponding to R 2 in the following formulas (II’-1) to (II’-8) is replaced by a methyl group. TIFF2025091391000069.tif46163Monomer (II’) is easily available from the market. The content of structural unit (II) is 0.5 to 20 mol%, preferably 0.5 to 18 mol%, more preferably 1 to 17 mol%, still more preferably 1 to 16 mol%, and still more preferably 1 to 10 mol% based on the total of all structural units of resin (A).

[0083] 〈Structural unit (a1)〉 Structural unit (a1) is derived from a monomer having an acid-labile group (hereinafter sometimes referred to as “monomer (a1)”). The acid-labile group contained in resin (A) is preferably a group represented by formula (1) (hereinafter also referred to as group (1)) and / or a group represented by formula (2) (hereinafter also referred to as group (2)). TIFF2025091391000070.tif2298[In formula (1), R a1, R a2 and R a3 each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group combining these, or R a1 and R a2 are bonded to each other to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with the carbon atom to which they are bonded, and the alkyl group, the alkenyl group, the alicyclic hydrocarbon group, and the aromatic hydrocarbon group may have a halogen atom. ma and na each independently represent 0 or 1, and at least one of ma and na represents 1. * represents a bonding site.] TIFF2025091391000071.tif2278[In formula (2), R a1’ and R a2’ each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R a3’ represents a hydrocarbon group having 1 to 20 carbon atoms, or R a2’ and R a3’ are bonded to each other to form a heterocyclic group having 3 to 20 carbon atoms together with the carbon atom to which they are bonded and X, and -CH2- contained in the hydrocarbon group and the heterocyclic group may be replaced by -O- or -S-, and the hydrocarbon group and the heterocyclic group may have a halogen atom. X represents an oxygen atom or a sulfur atom. na’ represents 0 or 1. * represents a bonding site.]

[0084] R a1 , R a2 and R a3 Examples of the alkyl group in R R a1 , R a2 and R a3Examples of the alkenyl group in [the compound] include ethenyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, tert-butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, isooctenyl group, and nonenyl group. R a1 , R a2 and R a3 The alicyclic hydrocarbon group in [the compound], R a1 , R a2 and R a3 may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, and cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group, and the following group (*represents the bonding site), etc. The number of carbon atoms of the alicyclic hydrocarbon group of R TIFF2025091391000072.tif10159R a1 , R a2 and R a3 Examples of the aromatic hydrocarbon group in [the compound], R include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, and phenanthryl group. Examples of the combined group include a group combining the above-mentioned alkyl group and alicyclic hydrocarbon group (for example, alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group, etc.), aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group, etc.), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group, etc.), aryl-cycloalkyl groups such as phenylcyclohexyl group, etc. Preferably, ma is 0 and na is 1. R a1 and Ra2 When -C(R a1 )(R a2 )(R a3 ) are bonded to each other to form an alicyclic hydrocarbon group, the following groups may be mentioned. The alicyclic hydrocarbon group preferably has 3 to 12 carbon atoms. * represents the bonding site with -O-. TIFF2025091391000073.tif27139

[0085] R a1’ 、R a2’ and R a3’ Examples of the hydrocarbon group in include alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups formed by combining these. Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and groups formed by combining these are the same as the groups mentioned for R a1 、R a2 and R a3 . R a2’ and R a3’ When are bonded to each other to form a heterocyclic group together with the carbon atom to which they are bonded and X, -C(R a1’ )(R a2’ )-X-R a3’ The following groups may be mentioned. * represents the bonding site. TIFF2025091391000074.tif19124R a1’ and R a2’ Among them, at least one of is preferably a hydrogen atom. na’ is preferably 0. R a1 、R a2 、R a3 、R a1 、R a2’ and R a3’ Examples of the halogen atom that may be possessed by include fluorine atom, chlorine atom, bromine atom or iodine atom.

[0086] Examples of group (1) include the following groups. In formula (1), R a1 、R a2and R a3 is an alkyl group, ma = 0, and a group where na = 1. As such a group, a tert-butoxycarbonyl group is preferred. In formula (1), R a1 , R a2 together with the carbon atom to which they are attached form an adamantyl group, and R a3 is an alkyl group, ma = 0, and a group where na = 1. In formula (1), R a1 and R a2 are each independently an alkyl group, R a3 is an adamantyl group, ma = 0, and a group where na = 1. Specific examples of group (1) include the following groups. * represents the bonding site. TIFF2025091391000075.tif151162

[0087] Specific examples of group (2) include the following groups. * represents the bonding site. TIFF2025091391000076.tif55153

[0088] Monomer (a1) is preferably a monomer having an acid-labile group and an ethylenically unsaturated bond, more preferably a (meth)acrylic monomer having an acid-labile group. Among the (meth)acrylic monomers having an acid-labile group, preferably those having an alicyclic hydrocarbon group with 5 to 20 carbon atoms can be mentioned. If a resin (A) having a structural unit derived from a monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in the resist composition, the resolution of the resist pattern can be improved.

[0089] Examples of the structural unit derived from the (meth)acrylic monomer having the group (1) include a structural unit represented by formula (a1-0) (hereinafter, sometimes referred to as structural unit (a1-0)), a structural unit represented by formula (a1-1) (hereinafter, sometimes referred to as structural unit (a1-1)), or a structural unit represented by formula (a1-2) (hereinafter, sometimes referred to as structural unit (a1-2)). Preferably, it is at least one structural unit selected from the group consisting of the structural unit (a1-0), the structural unit (a1-1) and the structural unit (a1-2), more preferably at least one or two structural units selected from the group consisting of the structural unit (a1-1) and the structural unit (a1-2). These may be used alone or in combination of two or more. TIFF2025091391000077.tif44144 [In formula (a1-0), formula (a1-1) and formula (a1-2), all symbols have the same meaning as above.]

[0090] R a01 , R a4 and R a5 The halogen atom in the formula (I) includes a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R a01 , R a4 and R a5 Examples of the alkyl group which may have a halogen atom in the above formula include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The number of carbon atoms in the alkyl group is preferably 1 to 4, more preferably 1 to 3, and even more preferably 1 or 2. The alkyl group is preferably a methyl group or an ethyl group, and more preferably a methyl group. R a01, R a4 and R a5 is preferably a hydrogen atom or a methyl group, more preferably a methyl group. L a01 , L a1 and L a2 is preferably an oxygen atom or *-O-(CH2) k01 -CO-O- (wherein k01 is preferably any integer from 1 to 4, more preferably 1), and more preferably an oxygen atom. R a02 , R a03 , R a04 , R a6 and R a7 Examples of the alkyl group, alkenyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and groups combining these in R a1 , R a2 and R a3 are the same as the groups exemplified by R R a02 , R a03 , and R a04 The alkyl group in R , R a6 and R a7 is preferably an alkyl group having 1 to 6 carbon atoms, more preferably a methyl group or an ethyl group, and still more preferably a methyl group. R a6 and R a7 The alkyl group in R , R a02 , R a03 , R a04 , R a6 and R a7 The number of carbon atoms of the alicyclic hydrocarbon group in R R a02 , R a03 , Ra04 , R a6 and R a7 The number of carbon atoms of the aromatic hydrocarbon group of R and R is preferably 6 to 12, more preferably 6 to 10. For the group combining an alkyl group and an alicyclic hydrocarbon group, it is preferable that the total number of carbon atoms of these alkyl group and alicyclic hydrocarbon group is 18 or less. For the group combining an alkyl group and an aromatic hydrocarbon group, it is preferable that the total number of carbon atoms of these alkyl group and aromatic hydrocarbon group is 18 or less. R a02 and R a03 are preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, and more preferably a methyl group, an ethyl group, a phenyl group or a naphthyl group which may have a halogen atom. R a04 is preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom or an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a halogen atom, and more preferably a methyl group, an ethyl group, a cyclohexyl group or an adamantyl group which may have a halogen atom. R a6 and R a7 are preferably an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkenyl group having 2 to 6 carbon atoms which may have a halogen atom or an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a halogen atom, and more preferably a methyl group, an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group, a phenyl group or a naphthyl group which may have a halogen atom, and still more preferably an ethyl group, an isopropyl group, a t-butyl group, an ethenyl group or a phenyl group which may have a halogen atom. m1' is preferably any integer from 0 to 3, more preferably 0 or 1. n1 is preferably any integer from 0 to 3, more preferably 0 or 1. n1' is preferably 0 or 1.

[0091] Examples of the structural unit (a1-0) include a structural unit represented by any of the formulas (a1-0-1) to (a1-0-24) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-0) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. Among them, the structural units represented by any of the formulas (a1-0-1) to (a1-0-10), formula (a1-0-13), formula (a1-0-14), and formulas (a1-0-19) to (a1-0-24) are preferred. a01 Examples of the structural unit (a1-1) include a structural unit derived from the monomers described in JP-A-2010-204646. Among them, a structural unit represented by any of the formulas (a1-1-1) to (a1-1-7) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group are preferred, and a structural unit represented by any of the formulas (a1-1-1) to (a1-1-4) is more preferred. TIFF2025091391000078.tif119160

[0092] Examples of the structural unit (a1-1) include a structural unit derived from the monomers described in JP-A-2010-204646. Among them, a structural unit represented by any of the formulas (a1-1-1) to (a1-1-7) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group are preferred, and a structural unit represented by any of the formulas (a1-1-1) to (a1-1-4) is more preferred. a4 Examples of the structural unit (a1-1) include a structural unit derived from the monomers described in JP-A-2010-204646. Among them, a structural unit represented by any of the formulas (a1-1-1) to (a1-1-7) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-1) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group are preferred, and a structural unit represented by any of the formulas (a1-1-1) to (a1-1-4) is more preferred. JPEG2025091391000079.jpg39169

[0093] Examples of the structural unit (a1-2) include a structural unit represented by any of the formulas (a1-2-1) to (a1-2-20) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-2) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. Among them, the structural units represented by any of the formulas (a1-2-2), (a1-2-5), (a1-2-6), and formulas (a1-2-10) to (a1-2-20) are preferred. a5 Examples of the structural unit (a1-2) include a structural unit represented by any of the formulas (a1-2-1) to (a1-2-20) and a structural unit in which the methyl group corresponding to R in the structural unit (a1-2) is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. Among them, the structural units represented by any of the formulas (a1-2-2), (a1-2-5), (a1-2-6), and formulas (a1-2-10) to (a1-2-20) are preferred. When the resin (A) contains the structural unit (a1-0) and / or the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin (A). Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 70 mol% or less, even more preferably 65 mol% or less. Specifically, it is 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, still more preferably 25 to 70 mol%, and even more preferably 30 to 70 mol%. When the resin (A) contains the structural unit (a1-0), the content thereof is 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, still more preferably 20 mol% or more, even more preferably 25 mol% or more, still even more preferably 30 mol% or more, and even more preferably 35 mol% or more, based on all the structural units of the resin (A). Also, it is 80 mol% or less, preferably 75 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less, and even more preferably 60 mol% or less. Specifically, it is 5 to 80 mol%, preferably 5 to 75 mol%, more preferably 10 to 70 mol%, still more preferably 10 to 65 mol%, and even more preferably 10 to 60 mol%. When the resin (A) contains the structural unit (a1-1) and / or the structural unit (a1-2), the total content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin (A). Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is 10 to 95 mol%, preferably 15 to 85 mol%, more preferably 15 to 80 mol%, still more preferably 20 to 80 mol%, even more preferably 20 to 75 mol%, still even more preferably 20 to 70 mol%, and even more preferably 20 to 55 mol%.

[0094] Examples of the structural unit having the group (2) in the structural unit (a1) include a structural unit represented by the formula (a1-4) (hereinafter sometimes referred to as "structural unit (a1-4)"). TIFF2025091391000081.tif31118[In the formula (a1-4), all the symbols have the same meanings as described above.]

[0095] R a1 And R a17 Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R a01 are the same as those exemplified by R of the formula (a1-0). R a1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group. R a17Examples of the alkoxy group in [compound name] include methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, sec-butoxy group, tert-butoxy group, pentyloxy group, and hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably an alkoxy group having 1 to 3 carbon atoms, still more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a17 Examples of the alkoxyalkyl group in [compound name] include methoxymethyl group, ethoxyethyl group, propoxymethyl group, isopropoxymethyl group, butoxymethyl group, sec-butoxymethyl group, and tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably an alkoxyalkyl group having 2 to 4 carbon atoms, still more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. R a17 Examples of the alkoxyalkoxy group in [compound name] include methoxymethoxy group, methoxyethoxy group, ethoxymethoxy group, ethoxyethoxy group, propoxymethoxy group, isopropoxymethoxy group, butoxymethoxy group, sec-butoxymethoxy group, and tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably an alkoxyalkoxy group having 2 to 4 carbon atoms, still more preferably a methoxyethoxy group or an ethoxyethoxy group. R a17 Examples of the alkylcarbonyl group in [compound name] include acetyl group, propionyl group, and butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 4 carbon atoms, more preferably an alkylcarbonyl group having 2 to 3 carbon atoms, and still more preferably an acetyl group. R a17 Examples of the alkylcarbonyloxy group in [compound name] include acetyloxy group, propionyloxy group, and butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 4 carbon atoms, more preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, and still more preferably an acetyloxy group. Ra17 is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxy methoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group.

[0096] A a11 Examples of the alkanediyl group of A include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, etc., and branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, heptane-1,6-diyl group, octane-1,7-diyl group, nonane-1,8-diyl group, decane-1,9-diyl group, undecane-1,10-diyl group, etc. The number of carbon atoms of the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, even more preferably 1 to 6, still more preferably 1 to 4, even still more preferably 1 to 3, and even more preferably 1 or 2. R a18 Examples of the alkyl group of R include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group and tert-butyl group. A a11 When -CH2- contained in the alkanediyl group of A is replaced by -O-, -CO- or -NR a18 -, the number of carbon atoms before replacement is taken as the number of carbon atoms of the alkanediyl group. A a11The -CH2- contained in the alkanediyl group is replaced by -O-, -CO- or -NR a18 Examples of the replaced group include a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an amino group (wherein -CH2- contained in the methyl group is replaced by -NR a18 -), an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylamino group (wherein any -CH2- contained in the alkyl group is replaced by -NR a18 -), a peptide group (wherein -CH2-CH2- contained in the ethylene group is replaced by -CO-NR a18 -), an alkanediyl-oxy group, an alkanediyl-oxycarbonyl group, an alkanediyl-carbonyl group, an alkanediyl-carbonyl-oxy group, an alkanediyl-sulfonyl group, an alkanediyl-thio group, an alkanediyl-amino group (wherein any -CH2- contained in the alkanediyl group is replaced by -NR a18 -), etc. These replaced groups include those similar to those exemplified herein, within the range allowed by the upper limit of the number of carbon atoms. Examples of the alkylamino group include an alkylamino group having 1 to 11 carbon atoms, such as a methylamino group, an ethylamino group, a propylamino group, a butylamino group, a pentylamino group, a hexylamino group, an octylamino group, etc. The number of carbon atoms of the alkylamino group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediylamino group include an alkanediylamino group having 1 to 11 carbon atoms, such as a methyleneamino group, an ethyleneamino group, a propyleneamino group, etc. The number of carbon atoms of the alkanediylamino group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. For example, A a11 The -CH2- contained in the alkanediyl group is replaced by -O-, -CO- or -NR a18 Examples of the replaced group include *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a12 -CO-O-, *-O-CO-Aa12 -O-, *-O-A a12 -CO-O-, *-CO-O-A a12 -O-CO-, *-O-CO-A a12 -O-CO-, *-CO-NR a18 - are exemplified. Among them, *-CO-O-, *-CO-O-A a12 -CO-O-, *-O-A a12 -CO-O-, *-CO-NR a18 - are preferred. Here, A a12 represents an alkanediyl group having 1 to 8 carbon atoms, and * represents the bonding site with the carbon atom to which R a1 is bonded. The alkanediyl group of A a12 includes alkanediyl groups similar to A a11 within the range allowed by the upper limit of the number of carbon atoms. A a11 is a single bond, *-CO-O- or *-CO-O-A a12 -CO-O- is preferred, a single bond, *-CO-O- or *-CO-O-CH2-CO-O- is more preferred, and a single bond or *-CO-O- is even more preferred. na1 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. na11 is preferably 0, 1, 2 or 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. mc is preferably 0 or 1.

[0097] R a34 、R a35 and R a36 The hydrocarbon groups in include alkyl groups, alicyclic hydrocarbon groups, aromatic hydrocarbon groups, and groups combining these. Examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, etc. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include decahydronaphthyl group, adamantyl group, norbornyl group and the following groups (* represents the bonding site). Examples of the aromatic hydrocarbon group include aryl groups such as phenyl group, naphthyl group, anthryl group, biphenyl group, phenanthryl group and the like. Examples of the combined group include a group formed by combining the above-mentioned alkyl group and alicyclic hydrocarbon group (for example, alkylcycloalkyl groups or cycloalkylalkyl groups such as methylcyclohexyl group, dimethylcyclohexyl group, methylnorbornyl group, cyclohexylmethyl group, adamantylmethyl group, adamantyldimethyl group, norbornylethyl group and the like), aralkyl groups such as benzyl group, aromatic hydrocarbon groups having an alkyl group (p-methylphenyl group, p-tert-butylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl group and the like), aromatic hydrocarbon groups having an alicyclic hydrocarbon group (p-cyclohexylphenyl group, p-adamantylphenyl group and the like), aryl-cycloalkyl groups such as phenylcyclohexyl group and the like. In particular, R a36 Examples thereof include an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these. R a35 and R a36 Examples of the divalent hydrocarbon group having 2 to 20 carbon atoms formed by bonding to each other and together with the -C-O- to which they are bonded include, for example, the following groups. * represents the bonding site, and one is the bonding site with R a34 TIFF2025091391000083.tif15105

[0098] R a34 is preferably a hydrogen atom.​ R a35 is preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms or an alicyclic hydrocarbon group having 3 to 12 carbon atoms, more preferably a methyl group or an ethyl group. R a36 's hydrocarbon group is preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms or a group formed by combining these, more preferably an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aralkyl group having 7 to 18 carbon atoms. R a36 The alkyl group and alicyclic hydrocarbon group in are preferably unsubstituted. R a36 The aromatic hydrocarbon group in preferably has an aromatic ring having an aryloxy group having 6 to 10 carbon atoms.

[0099] -O-C(R a34 )(R a35 )-O-R a36 in the structural unit (a1-4) is eliminated by contact with an acid (for example, p-toluenesulfonic acid) to form a hydroxy group or a carboxy group. -X a1 -O-C(R a34 )(R a35 )-O-R a36 In the case of a benzene ring, it may be bonded to any of the o-position, m-position or p-position with respect to the bonding position of A a11 . Among them, it is preferable that at least one is bonded to the o-position or p-position, and more preferably bonded to the p-position. In the case of a naphthalene ring, when the bonding position of A a11 is at the 1-position, it may be bonded to any of the 2nd to 8th positions, and when the bonding position of A a11 is at the 2nd position, it may be bonded to any of the 1st and 3rd to 8th positions. Among them, when the bonding position of A a11 is at the 1-position, it is preferable that at least one is bonded to the 3rd to 6th positions, and more preferably bonded to the 3rd or 4th position. When the bonding position of A a11 is at the 2nd position, it is preferable that it is bonded to the 4th to 7th positions, and more preferably bonded to the 5th or 6th position.

[0100] Examples of the structural unit (a1-4) include structural units derived from monomers described in JP-A-2010-204646. Preferably, the structural units represented by Formula (a1-4-1) to Formula (a1-4-42) and R in the structural unit (a1-4) a1 Examples of the structural unit in which the hydrogen atom corresponding to is replaced with a halogen atom, a haloalkyl group or an alkyl group include structural units represented by Formula (a1-4-1) to Formula (a1-4-5), Formula (a1-4-10), Formula (a1-4-13), Formula (a1-4-14), Formula (a1-4-19), and Formula (a1-4-20). When the resin (A) contains the structural unit (a1-4), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on the total of all the structural units of the resin (A). Further, 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is preferably 10 to 95 mol%, more preferably 15 to 90 mol%, still more preferably 20 to 85 mol%, still even more preferably 20 to 70 mol%, and particularly preferably 20 to 60 mol%.

[0101] Examples of the structural unit derived from the (meth)acrylic monomer having the group (2) also include the structural unit represented by Formula (a1-5) (hereinafter sometimes referred to as "structural unit (a1-5)"). TIFF2025091391000085.tif4558[In Formula (a1-5), all the symbols have the same meanings as described above.]

[0102] R a8Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom include R of formula (a1-0). a01 Examples thereof include the same ones as those exemplified above. In formula (a1-5), R a8 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. L 51 is preferably an oxygen atom. L 52 and L 53 Among them, it is preferable that one is -O- and the other is -S-. s1 is preferably 1. s1' is preferably any integer from 0 to 2. Z a1 is preferably a single bond or *-CH2-CO-O-.

[0103] Examples of the structural unit (a1-5) include structural units derived from monomers described in JP-A-2010-61117. Among them, the structural units represented by formula (a1-5-1) to formula (a1-5-4) are preferable, and the structural unit represented by formula (a1-5-1) or formula (a1-5-2) is more preferable. When the resin (A) contains the structural unit (a1-5), the content thereof is 1 mol% or more, preferably 2 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more, even more preferably 10 mol% or more, still even more preferably 20 mol% or more, and even more preferably 25 mol% or more, based on all the structural units of the resin (A). Further, it is 80 mol% or less, preferably 70 mol% or less, more preferably 60 mol% or less, still more preferably 50 mol% or less, even more preferably 45 mol% or less, still even more preferably 40 mol% or less, and even more preferably 30 mol% or less. Specifically, 1 to 50 mol% is preferable, 3 to 45 mol% is more preferable, 5 to 40 mol% is still more preferable, and 5 to 30 mol% is even more preferable.

[0104] Examples of the structural unit having the group (1) in the structural unit (a1) include a structural unit represented by the formula (a1-6) (hereinafter sometimes referred to as "structural unit (a1-6)"). TIFF2025091391000087.tif3481[In the formula (a1-6), all the symbols have the same meanings as described above.]

[0105] R a61 Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R a01 are the same as those exemplified above such as the formula (a1-0). R a61 is preferably a hydrogen atom, a methyl group or a trifluoromethyl group. R a62 、R a63 、R a64 and R a65 Examples of the alkyl group in include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group and the like. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group or an ethyl group. R a62 、R a63 and R a64 Examples of the cyclic hydrocarbon group in include an alicyclic hydrocarbon group and an aromatic hydrocarbon group. The alicyclic hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group and the like. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group and the like. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 16, more preferably 3 to 12. Examples of the aromatic hydrocarbon group include a phenylene group, a naphthylene group and the like. Examples of the substituent that the cyclic hydrocarbon group may have include a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. R a62 and R a63 Examples of the ring formed by bonding with each other include an adamantane ring, a cyclopentane ring, or a cyclohexane ring. Specifically, when R a62 and R a63 bond with each other to form a ring, examples of -C(R a62 )(R a63 )(R a64 ) include the following groups. * represents the bonding site with an oxygen atom. The number of carbon atoms in the ring is preferably 3 to 16, more preferably 3 to 12. TIFF2025091391000088.tif33111

[0106] L a61 and L a62 Examples of the alkanediyl group having 1 to 4 carbon atoms in L L a61 and L a62 include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, and the like. L a61 and L a62 are each independently preferably a methylene group or an ethylene group. X a61 is preferably a single bond or -CO-O-*, more preferably a single bond. X a62 is preferably a single bond or *-O-L a61 -, more preferably a single bond.

[0107] Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms for Ar include a phenylene group, 1-naphthylene group, 2-naphthylene group, 1-anthrylene group, 9-anthrylene group, biphenylene group, 1-phenanthrylene group, 2-phenanthrylene group, and the like. Examples of the substituent that the aromatic hydrocarbon group may have include a halogen atom, hydroxy group, alkyl group having 1 to 6 carbon atoms, alkoxy group having 1 to 6 carbon atoms, alkoxyalkyl group having 2 to 12 carbon atoms, alkoxyalkoxy group having 2 to 12 carbon atoms, alkylcarbonyl group having 2 to 4 carbon atoms, alkylcarbonyloxy group having 2 to 4 carbon atoms, acryloyloxy group, or methacryloyloxy group.

[0108] Examples of the halogen atom include a fluorine atom, iodine atom, chlorine atom, bromine atom, and the like. Examples of the alkyl group include a methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, and hexyl group. The alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. Examples of the alkoxy group include a methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, sec-butoxy group, tert-butoxy group, pentyloxy group, and hexyloxy group. The alkoxy group is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. Examples of the alkoxyalkyl group include a methoxymethyl group, ethoxyethyl group, propoxymethyl group, isopropoxymethyl group, butoxymethyl group, sec-butoxymethyl group, and tert-butoxymethyl group. The alkoxyalkyl group is preferably an alkoxyalkyl group having 2 to 8 carbon atoms, more preferably a methoxymethyl group or an ethoxyethyl group, and even more preferably a methoxymethyl group. Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a methoxyethoxy group or an ethoxyethoxy group. Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. Preferred substituents include a halogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms. More preferred are a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group. Even more preferred are a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. Ar is preferably a phenylene group which may have a substituent, more preferably a phenylene group which may have a hydroxy group.

[0109] Examples of the structural unit (a1-6) include structural units represented by Formula (a1-6-1) to Formula (a1-6-44). The structural units represented by Formula (a1-6-1) to Formula (a1-6-9) are preferred, the structural units represented by Formula (a1-6-1), Formula (a1-6-2), Formula (a1-6-4), Formula (a1-6-5), Formula (a1-6-7), or Formula (a1-6-8) are more preferred, and the structural units represented by Formula (a1-6-1) or Formula (a1-6-2) are even more preferred. In the following structural units, R a61A structural unit in which a hydrogen atom corresponding to is replaced with a methyl group or the like, and in the following structural units, R a61 A structural unit in which a methyl group corresponding to a61 is replaced with a hydrogen atom or the like is also cited as the structural unit (a1-6). TIFF2025091391000089.tif227164

[0110] When the resin (A) contains the structural unit (a1-6), its content is 3 mol% or more, preferably 5 mol% or more, more preferably 7 mol% or more, still more preferably 10 mol% or more, even more preferably 20 mol% or more, still even more preferably 30 mol% or more, and even more preferably 40 mol% or more, based on all the structural units of the resin (A). Also, 80 mol% or less is cited, preferably 75 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, still more preferably 7 to 70 mol%, even more preferably 7 to 65 mol%, and particularly preferably 10 to 65 mol%.

[0111] Also, examples of the structural unit (a1) include the following structural units. TIFF2025091391000090.tif33167

[0112] When the resin (A) contains structural units represented by the formulas (a1-7-1) to (a1-7-7), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin (A). Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, 10 to 95 mol% is preferable, 15 to 90 mol% is more preferable, 20 to 85 mol% is still more preferable, 20 to 70 mol% is even more preferable, and 20 to 60 mol% is particularly preferable.

[0113] In addition, examples of the structural unit (a1) also include the following structural units. TIFF2025091391000091.tif51120 When the resin (A) contains structural units represented by the formulas (a1-8-1) to (a1-8-3), the content thereof is 10 mol% or more, preferably 15 mol% or more, more preferably 20 mol% or more, still more preferably 25 mol% or more, even more preferably 30 mol% or more, still even more preferably 40 mol% or more, and even more preferably 50 mol% or more, based on all the structural units of the resin (A). Also, it is 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, even more preferably 75 mol% or less, still even more preferably 70 mol% or less, and even more preferably 60 mol% or less. Specifically, 10 to 60 mol% is preferable, 15 to 55 mol% is more preferable, 20 to 50 mol% is still more preferable, 20 to 45 mol% is even more preferable, and 20 to 40 mol% is particularly preferable.

[0114] In addition to the structural unit (II) and the structural unit (a1), the resin (A) may further contain structural units other than the structural unit (II) and the structural unit (a1). Examples of the structural units other than the structural unit (II) and the structural unit (a1) include structural units having no acid-labile group (hereinafter sometimes referred to as "structural unit (s)") and structural units known in the art.

[0115] 〈Structural unit (s)〉 The structural unit (s) is derived from a monomer having no acid-labile group (hereinafter sometimes referred to as "monomer (s)"). As the monomer that leads to the structural unit (s), a monomer having no acid-labile group known in the resist field can be used. The structural unit (s) preferably has a hydroxy group, a carboxy group or a lactone ring. A resin containing a structural unit having a hydroxy group or a carboxy group and having no acid-labile group (hereinafter sometimes referred to as "structural unit (a2)") and / or a structural unit having a lactone ring and having no acid-labile group (hereinafter sometimes referred to as "structural unit (a3)") is used in the resist composition of the present invention, whereby the resolution of the resist pattern and the adhesion to the substrate can be improved. In addition to the above-described structural units, the structural unit (s) includes a structural unit having a halogen atom (hereinafter sometimes referred to as "structural unit (a4)"), a structural unit having a non-leaving hydrocarbon group (hereinafter sometimes referred to as "structural unit (a5)"), a structural unit having a sultone structure (hereinafter sometimes referred to as "structural unit (a6)"), or a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (a7)").

[0116] 〈Structural unit (a2)〉 The structural unit (a2) is a structural unit represented by the formula (a2) and has an alcoholic hydroxy group, a phenolic hydroxy group or a carboxy group. TIFF2025091391000092.tif4094[In the formula (a2), R a2 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A a21 represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and -CH2- contained in the alkanediyl group may be replaced by -O-, -CO- or -NR a28 -. R a28 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. L a21 represents a single bond or a hydrocarbon group having 1 to 28 carbon atoms, the hydrocarbon group may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -CO-, -S- or -SO2-. L a22 represents a single bond or a chain hydrocarbon group having 1 to 12 carbon atoms which may have a fluorine atom, and -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-. na2 represents any integer from 1 to 5. When na2 is 2 or more, a plurality of L a22 may be the same as or different from each other.]

[0117] R a2 Examples of the halogen atom in R include a fluorine atom, an iodine atom, a chlorine atom, a bromine atom and the like. R a2 Examples of the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, an iodomethyl group and the like. The number of carbon atoms of the alkyl group is preferably 1 to 4, more preferably 1 to 3, and still more preferably 1 or 2. R a2is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and still more preferably a hydrogen atom or a methyl group.

[0118] A a21 Examples of the alkanediyl group of A include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, etc., and branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, heptane-1,6-diyl group, octane-1,7-diyl group, nonane-1,8-diyl group, decane-1,9-diyl group, undecane-1,10-diyl group, etc. The number of carbon atoms of the alkanediyl group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, even more preferably 1 to 4, still even more preferably 1 to 3, and still more preferably 1 or 2. R a28 Examples of the alkyl group of R include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group. A a21 When -CH2- contained in the alkanediyl group of A is replaced by -O-, -CO- or -NR a28 -, the number of carbon atoms before replacement is taken as the number of carbon atoms of the alkanediyl group. A a21 When -CH2- contained in the alkanediyl group of A is replaced by -O-, -CO- or -NR a28Examples of the group replacing - include a hydroxy group, a carboxy group, a carbonyl group, an oxy group, an amino group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylamino group, a peptide group, an alkanediyl-oxy group, an alkanediyl-oxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyl-oxy group, an alkanediylsulfonyl group, an alkanediylthio group, an alkanediylamino group, and the like. These replaced groups include the same groups as those exemplified in this specification within the range where the upper limit of the number of carbon atoms is allowed. Examples of the alkylamino group include alkylamino groups having 1 to 11 carbon atoms, such as a methylamino group, an ethylamino group, a propylamino group, a butylamino group, a pentylamino group, a hexylamino group, an octylamino group, and the like. The number of carbon atoms of the alkylamino group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediylamino group include alkanediylamino groups having 1 to 11 carbon atoms, such as a methyleneamino group, an ethyleneamino group, a propyleneamino group, and the like. The number of carbon atoms of the alkanediylamino group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Among them, A a21 Examples of the group in which -CH2- contained in the alkanediyl group of is replaced by -O-, -CO- or -NR a28 - include *-O-, *-CO-O-, *-O-CO-, *-CO-O-A a22 -CO-O-, *-O-CO-A a22 -O-, *-O-A a22 -CO-O-, *-CO-O-A a22 -O-CO-, *-O-CO-A a22 -O-CO-, *-CO-NR a28 - and the like. Among them, *-CO-O-, *-CO-O-A a22 -CO-O-, *-O-A a22 -CO-O-, *-CO-NR a28 - are preferred. Here, A a22represents an alkanediyl group having 1 to 8 carbon atoms, and * represents the bonding site to the carbon atom to which R a2 is bonded. The alkanediyl group of A a22 includes alkanediyl groups similar to those of A a21 within the range allowed by the upper limit of the number of carbon atoms. A a21 is preferably a single bond, *-CO-O- or *-CO-O-A a22 -CO-O-, more preferably a single bond, *-CO-O- or *-CO-O-CH2-CO-O-, and even more preferably a single bond or *-CO-O-.

[0119] The hydrocarbon group in L a21 is a (na2 + 1)-valent hydrocarbon group, and examples include linear or branched chain hydrocarbon groups, alicyclic hydrocarbon groups such as monocyclic or polycyclic (including spiro rings, condensed rings, bridged rings, etc.) alicyclic hydrocarbon groups, and cyclic hydrocarbon groups such as aromatic hydrocarbon groups. A group formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group or an aromatic hydrocarbon group and a chain hydrocarbon group) may also be used. L a21 Examples of the chain hydrocarbon group of include divalent to hexavalent chain hydrocarbon groups such as alkanediyl groups, alkanetriyl groups, alkanetetrayl groups, alkanepentayl groups, and alkanexayl groups. Examples of the alkanediyl group include alkanediyl groups similar to those of A a21 . Examples of the alkanetriyl group include methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group, pentanetriyl group, hexanetriyl group, heptanetriyl group, octanetriyl group, nonanetriyl group, decanetriyl group, undecanetriyl group, dodecanetriyl group, tridecanetriyl group, tetradecanetriyl group, pentadecanetriyl group, hexadecanetriyl group, and heptadecanetriyl group. Examples of the alkanetetrayl group include a methanetetrayl group, an ethanetetrayl group, a propanetetrayl group, a butanetetrayl group, a pentanetetrayl group, a hexanetetrayl group, a heptanetetrayl group, an octanetetrayl group, a nonanetetrayl group, a decanetetrayl group, an undecanetetrayl group, a dodecanetetrayl group, a tridecanetetrayl group, a tetradecanetetrayl group, a pentadecanetetrayl group, a hexadecanetetrayl group, a heptadecanetetrayl group, and the like. Examples of the alkanepentayl group include a methanepentayl group, an ethanepentayl group, a propanepentayl group, a butanepentayl group, a pentanepentayl group, a hexanepentayl group, and the like. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site. The number of carbon atoms in the chain hydrocarbon group is preferably from 1 to 18, more preferably from 1 to 12, still more preferably from 1 to 10, even more preferably from 1 to 9, still even more preferably from 1 to 8, still more preferably from 1 to 6, still even more preferably from 1 to 5, and particularly preferably from 1 to 4. L a21 Examples of the monocyclic and polycyclic alicyclic hydrocarbon groups in L include the following alicyclic hydrocarbon groups and the like. The bonding site can be at any position. TIFF2025091391000093.tif46168For example, divalent to hexavalent alicyclic hydrocarbon groups such as a cycloalkanediyl group, a cycloalkanetriyl group, a cycloalkanetetrayl group, a cycloalkanepentayl group, a cycloalkanexayl group, and the like can be mentioned. Specifically, Monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group, cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, cycloheptanetriyl group, cyclooctanetriyl group, cyclodecanetriyl group, cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, cycloheptanetetrayl group, cyclooctanetetrayl group, cyclodecanetetrayl group, and Polycyclic alicyclic hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, decahydronaphthalenediyl group, bicyclo[3.3.0]octanediy group, norbornanetriyl group, adamantanetriyl group, decahydronaphthalenetriyl group, bicyclo[3.3.0]octanetriyl group, norbornanetetrayl group, adamantanetetrayl group, decahydronaphthalenetetrayl group, bicyclo[3.3.0]octanetetrayl group are included. Also included are groups in which one or more hydrogen atoms of the above-described groups are replaced by a bonding site, and the like. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 20, more preferably 3 to 18, still more preferably 3 to 16, even more preferably 3 to 12, still even more preferably 6 to 12, and particularly preferably 6 to 10. L a21 Examples of the aromatic hydrocarbon group in L include divalent to hexavalent aromatic hydrocarbon groups such as arylene group, arenetriyl group, arenetetrayl group, arenepentayl group, arenexayl group, and the like. Specifically, phenylene group, naphthylene group, anthrylene group, biphenylene group, phenanthrylene group, benzenetriyl group, naphthalenetriyl group, anthracenetriyl group, biphenylenetriyl group, phenanthrenetriyl group, benzenetetrayl group, naphthalenetetrayl group, anthracenetetrayl group, biphenylenetetrayl group, phenanthrenetetrayl group, and the like can be mentioned. In addition, groups in which one or more of the hydrogen atoms of the above-described base are replaced with bonding sites can also be mentioned. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 20, more preferably 6 to 18, still more preferably 6 to 14, even more preferably 6 to 12, and even more preferably 6 to 10. Examples of the group formed by combining two or more types include a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group, a group formed by combining an aromatic hydrocarbon group and a chain hydrocarbon group, a group formed by combining an alicyclic hydrocarbon group and an aromatic hydrocarbon group, and a group formed by combining an alicyclic hydrocarbon group, a chain hydrocarbon group, and an aromatic hydrocarbon group. In the combination, the alicyclic hydrocarbon group, the aromatic hydrocarbon group, and the chain hydrocarbon group may each be combined with two or more types. Also, any group may be A a21 and L a22 and may be bonded thereto. Examples of groups in which -CH2- contained in a hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), a thiol group (a group in which -CH2- contained in a methyl group is replaced by -S-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkylthio group (a group in which -CH2- at any position contained in an alkyl group is replaced by -S-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylsulfonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -SO2-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an alkoxycarbonyloxy group (a group in which -CH2-CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-O-), an oxy group (a group in which -CH2- contained in a methylene group is replaced by -O-), a carbonyl group (a group in which -CH2- contained in a methylene group is replaced by -CO-), a thio group (a group in which -CH2- contained in a methylene group is replaced by -S-), a sulfonyl group (a group in which -CH2- contained in a methylene group is replaced by -SO2-), an alkanedioxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -CO-O-), an alkanediylsulfonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -SO2-),An alkanediylthio group (a group in which any -CH2- in the alkanediyl group is replaced by -S-), a cycloalkoxy group, a cycloalkylalkoxy group, an aromatic hydrocarbon group-carbonyl-oxy group, an aromatic hydrocarbon group-carbonyl group, an aromatic hydrocarbon group-oxy group, a group formed by combining two or more of these groups, etc. may be mentioned. Further, a group in which one or more hydrogen atoms of these groups are replaced at the bonding site, etc. may also be mentioned. Examples of the alkoxy group include alkoxy groups having 1 to 27 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, an undecyloxy group and the like. The number of carbon atoms of the alkoxy group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkylthio group include alkylthio groups having 1 to 27 carbon atoms, such as a methylthio group, an ethylthio group, a propylthio group, a butylthio group and the like. The number of carbon atoms of the alkylthio group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkoxycarbonyl group include alkoxycarbonyl groups having 2 to 27 carbon atoms, such as methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group and the like. Examples of the alkylcarbonyl group include alkylcarbonyl groups having 2 to 28 carbon atoms, such as acetyl group, propionyl group and butyryl group and the like. Examples of the alkylcarbonyloxy group include alkylcarbonyloxy groups having 2 to 27 carbon atoms, such as acetyloxy group, propionyloxy group, butyryloxy group and the like. Examples of the alkoxycarbonyloxy group include alkoxycarbonyloxy groups having 2 to 26 carbon atoms, such as butoxycarbonyloxy group and the like. The number of carbon atoms of the alkoxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyl group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkoxycarbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 27 carbon atoms, such as methylsulfonyl group, ethylsulfonyl group, propylsulfonyl group and the like. The number of carbon atoms of the alkylsulfonyl group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanedioxy group include alkanedioxy groups having 1 to 27 carbon atoms, such as methyleneoxy group, ethyleneoxy group, propanediioxy group, butanediioxy group, pentanediioxy group and the like. The number of carbon atoms of the alkanedioxy group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl-oxycarbonyl group include alkanediyl-oxycarbonyl groups having 2 to 27 carbon atoms, such as a methylene-oxycarbonyl group, an ethylene-oxycarbonyl group, a propanediyl-oxycarbonyl group, and a butanediyl-oxycarbonyl group. Examples of the alkanediyl-carbonyl group include alkanediyl-carbonyl groups having 2 to 28 carbon atoms, such as a methylene-carbonyl group, an ethylene-carbonyl group, a propanediyl-carbonyl group, a butanediyl-carbonyl group, and a pentanediyl-carbonyl group. Examples of the alkanediyl-carbonyloxy group include alkanediyl-carbonyloxy groups having 2 to 27 carbon atoms, such as a methylene-carbonyloxy group, an ethylene-carbonyloxy group, a propanediyl-carbonyloxy group, and a butanediyl-carbonyloxy group. The number of carbon atoms in the alkanediyl-oxycarbonyl group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediyl-carbonyl group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms in the alkanediyl-carbonyloxy group is preferably 2 to 11, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. Examples of the alkanediyl-thio group include alkanediyl-thio groups having 1 to 27 carbon atoms, such as a methylene-thio group, an ethylene-thio group, and a propanediyl-thio group. The number of carbon atoms in the alkanediyl-thio group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alkanediyl-sulfonyl group include alkanediyl-sulfonyl groups having 1 to 27 carbon atoms, such as a methylene-sulfonyl group, an ethylene-sulfonyl group, and a propylene-sulfonyl group. The number of carbon atoms in the alkanediyl-sulfonyl group is preferably 1 to 11, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3.

[0120] Examples of the cycloalkoxy group include cycloalkoxy groups having 3 to 27 carbon atoms, such as a cyclohexyloxy group. Examples of the cycloalkylalkoxy group include cycloalkylalkoxy groups having 4 to 27 carbon atoms, such as a cyclohexylmethoxy group. Examples of the aromatic hydrocarbon group-carbonyl-oxy group include aromatic hydrocarbon group-carbonyl-oxy groups having 7 to 27 carbon atoms, such as a benzoyloxy group. Examples of the aromatic hydrocarbon group-carbonyl group include aromatic hydrocarbon group-carbonyl groups having 7 to 28 carbon atoms, such as a benzoyl group. Examples of the aromatic hydrocarbon group-oxy group include aromatic hydrocarbon group-oxy groups having 6 to 27 carbon atoms, such as a phenyloxy group.

[0121] In addition, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include the following groups. Among the groups represented below, groups in which -O- is replaced by -S- and -CO- is replaced by -SO2- are also included. The bonding site can be at any position. Examples of the group in which -CH2- contained in the combined group is replaced by -O-, -S-, -CO- or -SO2- also include the following groups. The bonding site can be at any position. TIFF2025091391000095.tif26164L a21 The hydrocarbon group in [group name] may have one or more substituents. Examples of the substituent include a halogen atom, a haloalkyl group having 1 to 12 carbon atoms, an alkyl group having 1 to 16 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), an acryloyloxy group, a methacryloyloxy group, and the like. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. L a21The hydrocarbon group in can have a substituent such as a haloalkyl group by having a halogen atom as a substituent. Examples of the haloalkyl group include alkyl fluoride groups, alkyl chloride groups, alkyl bromide groups, alkyl iodide groups, etc. For example, chloromethyl group, bromomethyl group, iodomethyl group, fluoromethyl group, difluoromethyl group, trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluorobutyl group, etc. can be mentioned. The number of carbon atoms of the haloalkyl group is preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. L a21 The hydrocarbon group in can have a substituent such as a haloalkyl group by having a halogen atom as a substituent. Examples of the haloalkyl group include chloromethyl group, bromomethyl group, fluoromethyl group, difluoromethyl group, trifluoromethyl group, perfluorobutyl, etc. A haloalkyl group having 1 to 4 carbon atoms is preferred, and a haloalkyl group having 1 to 3 carbon atoms is more preferred. L a21 The hydrocarbon group of contains a branched structure, so that L a21 can have a substituent such as an alkyl group. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, 2-ethylhexyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, etc. The number of carbon atoms of the alkyl group is preferably 1 to 12, more preferably 1 to 10, still more preferably 1 to 8, even more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. L a21 The -CH2- contained in the hydrocarbon group of is replaced by a group such as -O- or -CO-, so that L a21can substantially have substituents such as a hydroxy group, a carboxy group, an alkoxy group, a thiol group, a sulfonyl group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkoxyalkyl group, an alkoxyalkoxy group, an acryloyloxy group, a methacryloyloxy group, etc. The number of carbon atoms of the alkoxy group is preferably 1 to 12, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. The number of carbon atoms of the alkoxycarbonyl group, the alkylcarbonyl group, and the alkylcarbonyloxy group is preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 to 3. The number of carbon atoms of the alkoxyalkyl group and the alkoxyalkoxy group is preferably 2 to 12, more preferably 2 to 8, still more preferably 2 to 6, and even more preferably 2 to 4. Examples of the above groups include the same ones as those exemplified in the present specification. L a21 The substituent that the hydrocarbon group in L may have is preferably a halogen atom, a haloalkyl group having 1 to 8 carbon atoms, or an alkyl group having 1 to 12 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), more preferably a halogen atom, a haloalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 10 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-), still more preferably a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms, a hydroxy group, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, even more preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even still more preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, a methoxy group, or an ethoxyethoxy group. Also, when the alkanediyl group of L is replaced by -O-, -CO-, etc., for example, *-L a21 -X a23 -X a21 -(La23 represents an alkanediyl group having 1 to 8 carbon atoms, and X a21 represents -O-, -O-CO-, -CO-O- or -O-CO-O-, and * represents the bonding site with A a21 . It is also preferable that it is as defined above.) L a21 is a single bond, an optionally substituted chain hydrocarbon group having 1 to 12 carbon atoms (however, -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an optionally substituted cyclic hydrocarbon group having 3 to 20 carbon atoms (however, -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or a group formed by combining an optionally substituted chain hydrocarbon group having 1 to 8 carbon atoms and an optionally substituted cyclic hydrocarbon group having 3 to 20 carbon atoms (however, -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-). It is preferably a single bond, an optionally substituted chain hydrocarbon group having 1 to 10 carbon atoms (however, -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (however, -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-), or a group formed by combining an optionally substituted chain hydrocarbon group having 1 to 6 carbon atoms and an optionally substituted cyclic hydrocarbon group having 3 to 18 carbon atoms (however, -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and -CH2- contained in the cyclic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-).

[0122] L a22Examples of the chain hydrocarbon group having 1 to 12 carbon atoms include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, etc., and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-dimethylpropane-1,3-diyl group, pentane-2,4-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group, etc. The number of carbon atoms of the chain hydrocarbon group is preferably 1 to 10, more preferably 1 to 8, still more preferably 1 to 6, and even more preferably 1 to 4. Examples of the group in which -CH2- contained in the chain hydrocarbon group is replaced by -O- or -CO- include those similar to those exemplified in the present specification as long as the upper limit of the number of carbon atoms permits. L a22 The fluorine atom(s) that L has may be one or two or more. na2 is preferably any integer from 1 to 4, and more preferably any integer from 1 to 3. L a21 Examples of the structural unit (a2) when L is a single bond or a chain hydrocarbon group include, for example, the following structural units. Among the following structural units, the structural unit in which the methyl group corresponding to R a2 is replaced by a hydrogen atom or the like is also a preferred structural unit of the structural unit (a2) in the same manner as the following structural units. When the resin (A) contains the above structural unit, its content is 1 mol% or more, preferably 5 mol% or more, more preferably 10 mol% or more, still more preferably 15 mol% or more, and even more preferably 20 mol% or more with respect to all the structural units of the resin (A). Also, it is preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less, even more preferably 60 mol% or less, still even more preferably 50 mol% or less, still more preferably 45 mol% or less, and even more preferably 40 mol% or less. Specifically, it is preferably 5 to 80 mol%, more preferably 10 to 70 mol%, still more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol%.

[0123] When producing a resist pattern from the resist composition of the present invention, when using a high-energy ray such as a KrF excimer laser (248 nm), an electron beam, or EUV (extreme ultraviolet light) as the exposure light source, as the structural unit (a2), a structural unit (a2) having a phenolic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-A) described later. Also, when using an ArF excimer laser (193 nm) or the like, as the structural unit (a2), a structural unit (a2) having an alcoholic hydroxy group is preferable, and it is more preferable to use the structural unit (a2-C) described later. The structural unit (a2) may be contained alone or in combination of two or more kinds.

[0124] In the structural unit (a2), L a21 In the case where is a cyclic hydrocarbon group, examples of the structural unit having a phenolic hydroxy group or a carboxy group include a structural unit represented by the formula (a2-A) (hereinafter sometimes referred to as "structural unit (a2-A)"). TIFF2025091391000097.tif30128[In the formula (a2-A), all the symbols have the same meanings as described above.]

[0125] Ra2 and A a21 is each a group similar to those exemplified by formula (a2). R a27 Examples of the halogen atom of R include a fluorine atom, a chlorine atom, an iodine atom, a bromine atom, and the like. R a27 Examples of the C1-C6 alkyl group which may have a halogen atom of R include a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a chloromethyl group, a bromomethyl group, and an iodomethyl group. The alkyl group is preferably a C1-C4 alkyl group, more preferably a C1-C3 alkyl group, still more preferably a methyl group or an ethyl group, and even more preferably a methyl group. R a27 Examples of the alkoxy group of R include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group. The alkoxy group is preferably a C1-C4 alkoxy group, more preferably a C1-C3 alkoxy group, still more preferably a methoxy group or an ethoxy group, and even more preferably a methoxy group. R a27 Examples of the alkoxyalkyl group of R include a methoxymethyl group, an ethoxyethyl group, a propoxymethyl group, an isopropoxymethyl group, a butoxymethyl group, a sec-butoxymethyl group, and a tert-butoxymethyl group. The alkoxyalkyl group is preferably a C2-C8 alkoxyalkyl group, more preferably a methoxymethyl group or an ethoxyethyl group, and still more preferably a methoxymethyl group. R a27Examples of the alkoxyalkoxy group include a methoxymethoxy group, a methoxyethoxy group, an ethoxymethoxy group, an ethoxyethoxy group, a propoxymethoxy group, an isopropoxymethoxy group, a butoxymethoxy group, a sec-butoxymethoxy group, and a tert-butoxymethoxy group. The alkoxyalkoxy group is preferably an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a methoxyethoxy group or an ethoxyethoxy group. R a27 Examples of the alkylcarbonyl group include an acetyl group, a propionyl group, and a butyryl group. The alkylcarbonyl group is preferably an alkylcarbonyl group having 2 to 3 carbon atoms, more preferably an acetyl group. R a27 Examples of the alkylcarbonyloxy group include an acetyloxy group, a propionyloxy group, and a butyryloxy group. The alkylcarbonyloxy group is preferably an alkylcarbonyloxy group having 2 to 3 carbon atoms, more preferably an acetyloxy group. R a27 is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms, or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group, or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, or an ethoxyethoxy group. nA2 is preferably 1, 2, 3, or 4, more preferably 1, 2, or 3, and even more preferably 1 or 2. na21 is preferably 0, 1, 2, or 3, more preferably 0, 1, or 2, and even more preferably 0 or 1. mc is preferably 0 or 1. -X a2 -OH, in the case of a benzene ring, may be bonded to any of the o-position, m-position, or p-position with respect to the bonding position of A a21 . Among them, at least one is preferably bonded to the m-position or p-position, more preferably bonded to the m-position. In the case of a naphthalene ring, A a21When the bonding position of is the 1st position, it may be bonded to any of the 2nd to 8th positions, A a21 When the bonding position of is the 2nd position, it may be bonded to the 1st position and any of the 3rd to 8th positions. Among them, A a21 When the bonding position of is the 1st position, at least one is preferably bonded to the 3rd to 6th positions, and more preferably bonded to the 3rd or 4th position. A a21 When the bonding position of is the 2nd position, it is preferably bonded to the 4th to 7th positions, and more preferably bonded to the 5th or 6th position.

[0126] Examples of the structural unit (a2-A) include structural units derived from monomers described in JP-A-2010-204634 and JP-A-2012-12577. Examples of the structural unit (a2-A) include structural units represented by formula (a2-2-1) to formula (a2-2-32), formula (a2-3-1) to formula (a2-3-24), and in the structural units represented by formula (a2-2-1) to formula (a2-2-32), formula (a2-3-1) to formula (a2-3-24), R in the structural unit (a2-A) a2 Examples include structural units in which the methyl group corresponding to is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or another alkyl group. TIFF2025091391000098.tif107170

[0127] When the structural unit (a2-A) is contained in the resin (A), the content of the structural unit (a2-A) is preferably 5 mol% or more, more preferably 10 mol% or more, still more preferably 15 mol% or more, and even more preferably 20 mol% or more, based on all the structural units. Also, it is preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 65 mol% or less, even more preferably 60 mol% or less, still even more preferably 50 mol% or less, still more preferably 45 mol% or less, and even more preferably 40 mol% or less. Specifically, it is preferably 5 to 80 mol%, more preferably 10 to 70 mol%, still more preferably 15 to 65 mol%, and even more preferably 20 to 65 mol%. The structural unit (a2-A) can be incorporated into the resin (A) by polymerizing a compound that induces the structural unit (a2-A) (for example, a compound (a2-A') in which the -CH2-C(-R a2 )- of the structural unit (a2-A) is in the state of CH2=C(-R a2 ) before cleavage). Also, for example, after polymerization using the structural unit (a1-4), it can be incorporated into the resin (A) by treatment with an acid such as p-toluenesulfonic acid. Further, after polymerization using acetoxystyrene or the like, the structural unit (a2-A) can be incorporated into the resin (A) by treatment with an alkali such as tetramethylammonium hydroxide.

[0128] In the structural unit (a2), when L a21 is a cyclic hydrocarbon group, examples of the structural unit having an alcoholic hydroxy group or a carboxy group include the structural unit represented by the formula (a2-B) (hereinafter sometimes referred to as "structural unit (a2-B)"), the structural unit represented by the formula (a2-C) (hereinafter sometimes referred to as "structural unit (a2-C)"), and the structural unit represented by the formula (a2-D) (hereinafter sometimes referred to as "structural unit (a2-D)"). In formulas (a2-B) and (a2-C), R a2 represents the same meaning as in formula (a2). R a27 represents the same meaning as in formula (a2-A). L a25 represents -O- or *-O-(CH2) k2 -CO-O-, and k2 represents an integer from 1 to 7. * represents the bonding site with -CO-. X a2 represents a single bond or -CO-. R a25 and R a26 each independently represents a hydrogen atom, a methyl group, or a hydroxy group. nB2 represents an integer from 1 to 5. When nB2 is 2 or more, the plurality of X a2 may be the same as or different from each other. nB22 represents an integer from 0 to 8. When nB22 is 2 or more, the plurality of R a27 may be the same as or different from each other. nC22 represents an integer from 0 to 10. When nC22 is 2 or more, the plurality of R a27 may be the same as or different from each other.] L a25 is preferably -O-, -O-(CH2) f1 -CO-O- (where f1 represents an integer from 1 to 4), and more preferably -O-. R a2 is preferably a methyl group. X a2 is preferably a single bond. R a25 is preferably a hydrogen atom. R a26 is preferably a hydrogen atom or a hydroxy group. R a27is preferably a halogen atom, a hydroxy group, a carboxy group, an optionally halogenated alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxymethoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group. nB2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, and even more preferably 1 or 2. nB22 is preferably any integer from 0 to 3, more preferably 0, 1 or 2, and even more preferably 0 or 1. nC22 is preferably any integer from 0 to 6, more preferably any integer from 0 to 3, and even more preferably 0 or 1.

[0129] Examples of the structural unit (a2-B) and the structural unit (a2-C) include structural units derived from the monomers described in JP-A-2010-204646, the following structural units, and methyl groups or hydrogen atoms corresponding to R in the following structural units, which are replaced by hydrogen atoms, halogen atoms, haloalkyl groups or other alkyl groups. Among them, the structural units represented by any of formula (a2-B-1) to formula (a2-B-5) and formula (a2-C-1) to formula (a2-C-9) are preferable. a2 When the resin (A) contains the structural unit (a2-B) or the structural unit (a2-C), the content thereof is 1 mol% or more, preferably 2 mol% or more, based on all the structural units of the resin (A). Further, it is 45 mol% or less, preferably 40 mol% or less, more preferably 35 mol% or less, even more preferably 20 mol% or less, and still more preferably 10 mol% or less. Specifically, it is 1 to 45 mol%, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, even more preferably 1 to 20 mol%, and still more preferably 1 to 10 mol%. TIFF2025091391000101.tif80164 When the resin (A) contains the structural unit (a2-B) or the structural unit (a2-C), the content thereof is 1 mol% or more, preferably 2 mol% or more, based on all the structural units of the resin (A). Further, it is 45 mol% or less, preferably 40 mol% or less, more preferably 35 mol% or less, even more preferably 20 mol% or less, and still more preferably 10 mol% or less. Specifically, it is 1 to 45 mol%, preferably 1 to 40 mol%, more preferably 1 to 35 mol%, even more preferably 1 to 20 mol%, and still more preferably 1 to 10 mol%.

[0130] TIFF2025091391000102.tif51106[In formula (a2-D), R a2 and A a21 each represent the same meaning as formula (a2). R a27 represents the same meaning as formula (a2-A). R a21 and R a22 each independently represent an alkyl fluoride group having 1 to 4 carbon atoms. L a24 represents a single bond or an alkanediyl group having 1 to 3 carbon atoms, and the alkanediyl group may be substituted with a fluorine atom. nD2 represents any integer from 1 to 5. When nD2 is 2 or more, the groups in the plurality of parentheses may be the same as or different from each other. nD22 represents any integer from 0 to 4. When nD22 is 2 or more, the plurality of R a27 may be the same as or different from each other. However, 1 ≦ nD2 + nD22 ≦ 5.] R a21 and R a22 As the alkyl fluoride groups of, each independently, a trifluoromethyl group, 2,2,2-trifluoroethyl group, 3,3,3-trifluoropropyl group, 4,4,4-trifluorobutyl group and the like can be mentioned. R a21 and R a22 are preferably a trifluoromethyl group. L a24 As the alkanediyl group of, a methylene group, ethane-1,1-diyl group, propane-1,1-diyl group, propane-2,2-diyl group and the like can be mentioned. L a24 is preferably a single bond or a methylene group. R a27is preferably a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 4 carbon atoms or an alkoxyalkoxy group having 2 to 8 carbon atoms, more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group, an ethoxy group, an ethoxyethoxy group or an ethoxy methoxy group, and even more preferably a fluorine atom, an iodine atom, a hydroxy group, a methyl group, a methoxy group or an ethoxyethoxy group. nD2 is preferably 1, 2, 3 or 4, more preferably 1, 2 or 3, even more preferably 1 or 2, and even more preferably 1. Further, preferably, nD2 is 1 and the group in parentheses is bonded to the para position. nD22 is preferably any integer from 0 to 3, more preferably any integer from 0 to 2, even more preferably 0 or 1, and even more preferably 0.

[0131] As the structural unit (a2-D), a structural unit represented by the following formula (a2-D1) (hereinafter sometimes referred to as "structural unit (a2-D1)") is more preferable. TIFF2025091391000103.tif51107[In formula (a2-D1), R a2 、A a21 、R a27 、nD2 and nD22 represent the same meanings as in formula (a2-D).] In formula (a2-D1), R a2 is preferably a hydrogen atom or a methyl group. A a21 is preferably a single bond.

[0132] Examples of the structural unit (a2-D) include the structural units described below. TIFF2025091391000104.tif62167In the structural units represented by formula (a2-D-1) to formula (a2-D-8), the hydrogen atom corresponding to R a2 is replaced with a methyl group or the like, and in the structural units represented by formula (a2-D-9) to formula (a2-D-16), Ra2 Structural units in which the methyl group corresponding to a2 is replaced by a hydrogen atom or the like can also be cited as specific examples of the structural unit (a2-D). Among them, the structural units represented by the formulas (a2-D-1) to (a2-D-8) are preferable, the structural units represented by the formulas (a2-D-1) to (a2-D-4) are more preferable, and the structural unit represented by the formula (a2-D-1) is even more preferable.

[0133] When the resin (A) contains the structural unit (a2-D), the content thereof is preferably 3 mol% or more, more preferably 5 mol% or more, still more preferably 10 mol% or more, based on all the structural units of the resin (A). Also, it is preferably 80 mol% or less, more preferably 75 mol% or less, still more preferably 70 mol% or less, and even more preferably 65 mol% or less. Specifically, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, still more preferably 10 to 70 mol%, and even more preferably 10 to 65 mol%.

[0134] 〈Structural unit (a3)〉 The lactone ring of the structural unit (a3) may be a monocyclic ring such as a β-propiolactone ring, a γ-butyrolactone ring, or a δ-valerolactone ring, or may be a condensed ring of a monocyclic lactone ring and another ring. Preferably, a γ-butyrolactone ring, an adamantane lactone ring, or a bridged ring containing a γ-butyrolactone ring structure (for example, the structural unit represented by the following formula (a3-2)) can be cited. The structural unit (a3) is preferably a structural unit represented by the formula (a3-1), the formula (a3-2), the formula (a3-3), or the formula (a3-4). These may be contained alone or in combination of two or more. TIFF2025091391000105.tif51164[In the formulas (a3-1), (a3-2), (a3-3), and (a3-4), L a4 、L a5 and L a6 each independently represents a group represented by -O- or *-O-(CH2) k3 -CO-O- (where k3 represents an integer of 1 to 7). L a7 represents -O-, *-O-L a8 -O-, *-O-L a8 -CO-O-, *-O-L a8 -CO-O-L a9 -CO-O- or *-O-L a8 -O-CO-L a9 represents -O-. L a8 and L a9 each independently represents an alkanediyl group having 1 to 6 carbon atoms. * represents the bonding site with the carbonyl group. R a18 R a19 R a20 and R a24 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X a3 represents -CH2- or an oxygen atom. R a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms. R a22 R a23 and R a25 each independently represents a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms. p1 represents any integer from 0 to 5. q1 represents any integer from 0 to 3. r1 represents any integer from 0 to 3. w1 represents any integer from 0 to 8. When p1, q1, r1, and / or w1 is 2 or more, the plural Rs a21 R a22 R a23 and / or R a25 may be the same as or different from each other.

[0135] R a21 R a22 R a23 and R a25Examples of the aliphatic hydrocarbon group in include alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, and a tert-butyl group. R a18 , R a19 , R a20 and R a24 Examples of the halogen atom and the alkyl group optionally having a halogen atom in the formula (a1-0) include R a01 The same examples as those exemplified above are included. L a8 and L a9 Examples of the alkanediyl group in the formula (I) include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, a pentane-1,4-diyl group, and a 2-methylbutane-1,4-diyl group. L a4 ~L a6 are each independently preferably -O- or *-O-(CH2) k3 In the -CO-O- group, k3 is a group in which k3 is any integer of 1 to 4, more preferably -O- and *-O-CH2-CO-O-, and further preferably an oxygen atom. L a7 is preferably -O- or *-OL a8 It is —CO—O—, and more preferably —O—, —O—CH2—CO—O— or —O—C2H4—CO—O—. R a18 , R a19 , R a20 and R a24 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group, or an ethyl group, and even more preferably a hydrogen atom or a methyl group. R a21 is preferably a methyl group. R a22 , R a23 and R a25Each is independently, preferably a carboxy group, a cyano group or a methyl group. p1, q1 and r1 are each independently, preferably any integer from 0 to 2, more preferably 0 or 1. w1 is preferably any integer from 0 to 2, more preferably 0 or 1. In particular, formula (a3-4) is preferably formula (a3-4)’. TIFF2025091391000106.tif4051 (wherein R a24 , L a7 has the same meaning as described above.)

[0136] Examples of the structural unit (a3) include structural units derived from the monomers described in JP-A-2010-204646, the monomers described in JP-A-2000-122294, and the monomers described in JP-A-2012-41274. Examples of the structural unit (a3) include structural units represented by any of formula (a3-1-1), formula (a3-1-2), formula (a3-2-1), formula (a3-2-2), formula (a3-3-1), formula (a3-3-2) and formula (a3-4-1) to formula (a3-4-12), and in the above structural units, the methyl groups corresponding to R a18 , R a19 , R a20 and R a24 are replaced by hydrogen atoms are preferred. When the resin (A) contains the structural unit (a3), the total content thereof is 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, still more preferably 10 mol% or more, based on all the structural units of the resin (A). Further, it is 70 mol% or less, preferably 65 mol% or less, more preferably 60 mol% or less, still more preferably 50 mol% or less, even more preferably 40 mol% or less, still even more preferably 30 mol% or less, still more preferably 25 mol% or less, and still even more preferably 20 mol% or less. Specifically, it is 1 to 70 mol%, preferably 3 to 70 mol%, more preferably 3 to 65 mol%, still more preferably 5 to 65 mol%, even more preferably 5 to 60 mol%, and still even more preferably 10 to 60 mol%. Further, the content of the structural unit (a3-1), the structural unit (a3-2), the structural unit (a3-3), or the structural unit (a3-4) is preferably 1 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more, and still even more preferably 10 mol% or more, based on all the structural units of the resin (A). Further, it is preferably 60 mol% or less, more preferably 55 mol% or less, still more preferably 50 mol% or less, even more preferably 40 mol% or less, still even more preferably 30 mol% or less, still more preferably 25 mol% or less, and still even more preferably 20 mol% or less. Specifically, 1 to 60 mol% is preferable, 3 to 60 mol% is more preferable, 3 to 55 mol% is still more preferable, 5 to 55 mol% is still even more preferable, 5 to 50 mol% is even more preferably, and 10 to 50 mol% is still even more preferable.

[0137] 〈Structural unit (a4)〉 The structural unit represented by the formula (a4) is shown below. TIFF2025091391000108.tif3355[In the formula (a4), R 41 represents a hydrogen atom or a methyl group. R42 represents a saturated hydrocarbon group having a halogen atom with 1 to 24 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-.

[0138] R 42 The saturated hydrocarbon group represented by includes a linear or branched chain saturated hydrocarbon group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, and a group formed by combining these, etc. Examples of the chain saturated hydrocarbon group include linear alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, dodecyl group, pentadecyl group, hexadecyl group, heptadecyl group and octadecyl group, and branched alkyl groups such as isopropyl group and isobutyl group. Examples of the monocyclic or polycyclic alicyclic saturated hydrocarbon group include monocyclic alicyclic saturated hydrocarbon groups which are monocyclic cycloalkyl groups such as cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group; polycyclic alicyclic saturated hydrocarbon groups which are polycyclic cycloalkyl groups such as decahydronaphthyl group, adamantyl group, norbornyl group and the following group (* represents the bonding site). Examples of the group formed by the combination include a group formed by combining one or more alkyl groups or one or more alkanediyl groups with one or more alicyclic saturated hydrocarbon groups, and -alkanediyl group-alicyclic saturated hydrocarbon group, -alicyclic saturated hydrocarbon group-alkyl group, -alkanediyl group-alicyclic saturated hydrocarbon group-alkyl group, etc. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group; branched alkanediyl groups such as propane-1,2-diyl group, butane-1,3-diyl group, 2-methylpropane-1,2-diyl group, 1-methylbutane-1,4-diyl group, 2-methylbutane-1,4-diyl group. The terminal of the branched alkanediyl group may be a methyl group. R 42 Examples of the halogen atom in the saturated hydrocarbon group contained in R include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. R 42 Examples of the group in which -CH2- of the saturated hydrocarbon group contained in R is replaced by -O- or -CO- include a hydroxy group (a group in which -CH2- contained in a methyl group is replaced by -O-), a carboxy group (a group in which -CH2-CH2- contained in an ethyl group is replaced by -O-CO-), a carbonyl group (a group in which -CH2- contained in a methylene group is replaced by -CO-), an oxy group (a group in which -CH2- contained in a methylene group is replaced by -O-), an alkoxy group (a group in which -CH2- at any position contained in an alkyl group is replaced by -O-), an alkoxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -O-CO-), an alkylcarbonyl group (a group in which -CH2- at any position contained in an alkyl group is replaced by -CO-), an alkylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkyl group is replaced by -CO-O-), an alkanedioxy group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -O-), an alkanedioxycarbonyl group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -O-CO-), an alkanediylcarbonyl group (a group in which -CH2- at any position contained in an alkanediyl group is replaced by -CO-), an alkanediylcarbonyloxy group (a group in which -CH2-CH2- at any position contained in an alkanediyl group is replaced by -CO-O-), a cycloalkoxy group, a cycloalkylalkoxy group, a group formed by combining two or more of these groups, and the like. These replaced groups include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits.

[0139] As the structural unit (a4), R 42 is preferably a saturated hydrocarbon group having a fluorine atom, and R 42Examples of the structural unit (a4) which is a saturated hydrocarbon group having a fluorine atom include a structural unit represented by the formula (a4-1) (hereinafter sometimes referred to as "structural unit (a4-1)"), a structural unit represented by the formula (a4-2) (hereinafter sometimes referred to as "structural unit (a4-2)"), a structural unit represented by the formula (a4-3) (hereinafter sometimes referred to as "structural unit (a4-3)"), and a structural unit represented by the formula (a4-A) (hereinafter sometimes referred to as "structural unit (a4-A)"). The structural unit represented by the formula (a4-1) is the structural unit shown below. TIFF2025091391000110.tif4864[In the formula (a4-1), R 41 represents a hydrogen atom or a methyl group. L 41 represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. L 42f represents an alkanediyl group having 1 to 8 carbon atoms and having a fluorine atom or a cycloalkanediyl group having 3 to 12 carbon atoms and having a fluorine atom. R 42f represents a hydrogen atom or a fluorine atom.]

[0140] L 41 Examples of the alkanediyl group in include linear alkanediyl groups such as a methylene group, an ethylene group, a propane-1,3-diyl group, and a butane-1,4-diyl group, and branched alkanediyl groups such as an ethane-1,1-diyl group, a propane-1,2-diyl group, a butane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, and a 2-methylpropane-1,2-diyl group. The terminal of the branched alkanediyl group may be a methyl group. L 42fExamples of the alkanediyl group having a fluorine atom in [L] include linear alkanediyl groups having a fluorine atom such as a methylene group having a fluorine atom, an ethylene group having a fluorine atom, a propane-1,3-diyl group having a fluorine atom, a butane-1,4-diyl group having a fluorine atom, a pentane-1,5-diyl group having a fluorine atom, a hexane-1,6-diyl group having a fluorine atom, a heptane-1,7-diyl group having a fluorine atom, and an octane-1,8-diyl group having a fluorine atom; Examples of the branched alkanediyl group having a fluorine atom include an ethane-1,1-diyl group having a fluorine atom, a propane-1,1-diyl group having a fluorine atom, a propane-1,2-diyl group having a fluorine atom, a propane-2,2-diyl group having a fluorine atom, a pentane-2,4-diyl group having a fluorine atom, a 2-methylpropane-1,3-diyl group having a fluorine atom, a 2-methylpropane-1,2-diyl group having a fluorine atom, a pentane-1,4-diyl group having a fluorine atom, and a 2-methylbutane-1,4-diyl group having a fluorine atom. The terminal of the branched alkanediyl group may be a methyl group which may have a fluorine atom. L 42f Examples of the cycloalkanediyl group having a fluorine atom in [L] include monocyclic cycloalkanediyl groups having a fluorine atom such as a cyclobutane-1,3-diyl group having a fluorine atom, a cyclopentane-1,3-diyl group having a fluorine atom, a cyclohexane-1,4-diyl group having a fluorine atom, a cyclohexene-3,6-diyl group having a fluorine atom, a cycloheptane-1,4-diyl group having a fluorine atom, and a cyclooctane-1,5-diyl group having a fluorine atom, and polycyclic cycloalkanediyl groups having a fluorine atom such as a norbornane-1,4-diyl group having a fluorine atom, a norbornane-2,5-diyl group having a fluorine atom, a 5-norbornene-2,3-diyl group having a fluorine atom, an adamantane-1,5-diyl group having a fluorine atom, and an adamantane-2,6-diyl group having a fluorine atom. L 42fThe number of fluorine atoms in the alkanediyl group and the cycloalkanediyl group having a fluorine atom is preferably 1 or more, and more preferably 2 or more. L 42f The alkanediyl group and the cycloalkanediyl group having a fluorine atom in are preferably a perfluoroalkanediyl group and a perfluorocycloalkanediyl group, respectively.

[0141] L 42f Examples of the perfluoroalkanediyl group in include a difluoromethylene group, a perfluoroethylene group, a perfluoroethylfluoromethylene group, a perfluoropropane-1,3-diyl group, a perfluoropropane-1,2-diyl group, a perfluoropropane-2,2-diyl group, a perfluorobutane-1,4-diyl group, a perfluorobutane-2,2-diyl group, a perfluorobutane-1,2-diyl group, a perfluoropentane-1,5-diyl group, a perfluoropentane-2,2-diyl group, a perfluoropentane-3,3-diyl group, a perfluorohexane-1,6-diyl group, a perfluorohexane-2,2-diyl group, a perfluorohexane-3,3-diyl group, a perfluoroheptane-1,7-diyl group, a perfluoroheptane-2,2-diyl group, a perfluoroheptane-3,4-diyl group, a perfluoroheptane-4,4-diyl group, a perfluorooctane-1,8-diyl group, a perfluorooctane-2,2-diyl group, a perfluorooctane-3,3-diyl group, a perfluorooctane-4,4-diyl group, and the like. L 42f Examples of the perfluorocycloalkanediyl group in include a perfluorocyclohexanediyl group, a perfluorocyclopentanediyl group, a perfluorocycloheptanediyl group, a perfluoroadamantanediyl group, and the like.

[0142] L 41 is preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms, more preferably a single bond, a methylene group or an ethylene group, and even more preferably a single bond or a methylene group. L 42fis preferably a perfluoroalkanediyl group having 1 to 8 carbon atoms or a perfluorocycloalkanediyl group having 3 to 12 carbon atoms, more preferably a perfluoroalkanediyl group having 1 to 6 carbon atoms, and still more preferably a perfluoroalkanediyl group having 1 to 3 carbon atoms.

[0143] As the structural unit (a4-1), there may be mentioned the structural units shown below and the structural units in the structural unit (a4-1) in the following structural units where the methyl group corresponding to R 41 is replaced by a hydrogen atom. The structural unit represented by the formula (a4-2) is the structural unit shown below. TIFF2025091391000112.tif5574 [In the formula (a4-2), R 41 represents a hydrogen atom or a methyl group. L 43f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. R 43f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. However, at least one of L 43f and R 43f has a fluorine atom, and the upper limit of the total number of carbon atoms of L 43f and R 43f is 21.]

[0144] Examples of the saturated hydrocarbon group in L 43f and R 43f include linear or branched chain saturated hydrocarbon groups, monocyclic or polycyclic alicyclic saturated hydrocarbon groups, and groups formed by combining these. Examples of the saturated hydrocarbon group in L 43f and R 43f are, as long as the upper limit of the total number of carbon atoms of L 43f and R 43f allows, R in the formula (a4)42 Examples thereof include the same groups as the saturated hydrocarbon groups exemplified as the saturated hydrocarbon group of

[0145] L 43f As the saturated hydrocarbon group of TIFF2025091391000113.tif14120 [In the formula (L43f-1), s represents 0 or 1. L 45f and L 46f each independently represent a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a fluorine atom. L 47f represents a single bond or a divalent saturated hydrocarbon group having 1 to 5 carbon atoms which may have a fluorine atom. X 46f and X 47f each independently represent -O-, -CO-, -CO-O- or -O-CO-. However, the total number of carbon atoms of L 45f , L 46f , L 47f , X 46f and X 47f is 7 or less. * and ** are bonding sites, and ** is the bonding site with -O-CO-R 43f

[0146] Examples of the divalent saturated hydrocarbon group represented by L 45f , L 46f and L 47f in the group represented by the formula (L43f-1) include linear or branched alkanediyl groups, monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups, and divalent saturated hydrocarbon groups formed by combining an alkanediyl group and a divalent alicyclic saturated hydrocarbon group. Specifically, examples include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a 1-methylpropane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a 2-methylpropane-1,2-diyl group, and the like. ​s is preferably 0. Examples of the group represented by the formula (L43f-1) include the following groups. In the following examples, * and ** each represent a bonding site, and ** is -O-CO-R 43f and is the bonding site with -O-CO-R. TIFF2025091391000114.tif47140

[0147] R 43f is preferably a saturated hydrocarbon group having a fluorine atom. In this case, examples of the structural unit represented by the formula (a4-2) include the structural units represented by the formula (a4-2A) or (formula a4-2B). TIFF2025091391000115.tif69102[In the formula (a4-2A) and the formula (a4-2B), R 41 and L 43f represent the same as those in the formula (a4-2). R 43fA represents a saturated hydrocarbon group having 1 to 20 carbon atoms and having a fluorine atom. A 43f represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. X 43 represents **-O-CO- or **-CO-O-, and ** represents the bonding site with A 43f and is the bonding site with A. R 43fB represents a saturated hydrocarbon group having 1 to 17 carbon atoms which may have a fluorine atom. However, in the formula (a4-2A), the total number of carbon atoms of L 43f and R 43fA is 21 or less, and in the formula (a4-2B), the total number of carbon atoms of L 43f , A 43f , X 43 and R 43fB is 21 or less, and at least one of A 43f and R 43fB has at least one fluorine atom. R 43fAThe saturated hydrocarbon group is, as long as the upper limit of the number of carbon atoms permits, the same saturated hydrocarbon group as the saturated hydrocarbon group exemplified by R 42 and includes saturated hydrocarbon groups similar to the saturated hydrocarbon groups exemplified by 42 . R 43fA is preferably an alkyl group having 1 to 13 carbon atoms and having a fluorine atom, a cycloalkyl group having 3 to 12 carbon atoms and having a fluorine atom, or a group combining them, *-(CF2) n43f -R 42’ (* represents the bonding site with the carbonyl group. n43f represents any integer from 1 to 6. R 42’ represents a hydrogen atom or a fluorine atom.) or a perfluorocycloalkyl group having 3 to 12 carbon atoms is more preferable. A 43f and the saturated hydrocarbon group of R 43fB are, as long as the upper limit of the number of carbon atoms permits, the same saturated hydrocarbon groups as the saturated hydrocarbon groups exemplified by R 42 in formula (a4). A 43f is preferably a divalent chain-like saturated hydrocarbon group which may have a fluorine atom, a divalent alicyclic saturated hydrocarbon group, or a group combining them, more preferably a divalent chain-like saturated hydrocarbon group having a fluorine atom, and even more preferably a fluorinated alkanediyl group having 1 to 6 carbon atoms. R 43fBThe saturated hydrocarbon group which may have a fluorine atom is preferably a chain saturated hydrocarbon group, an alicyclic saturated hydrocarbon group or a combination thereof which may have a fluorine atom, more preferably an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms or a combination thereof which may have a fluorine atom, and still more preferably a trifluoromethyl group, a difluoromethyl group, a methyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1,2,2-tetrafluoroethyl group, an ethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a propyl group, a perfluorobutyl group, a 1,1,2,2,3,3,4,4-octafluorobutyl group, a butyl group, a perfluoropentyl group, a 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, a pentyl group, a hexyl group, a perfluorohexyl group, a heptyl group, a perfluoroheptyl group, an octyl group, a perfluorooctyl group and other alkyl fluoride groups, a cyclopropylmethyl group, a cyclopropyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, a perfluorocyclohexyl group, an adamantyl group, an adamantylmethyl group, an adamantyldimethyl group, a norbornyl group, a norbornylmethyl group, a perfluoroadamantyl group, a perfluoroadamantylmethyl group and the like. In formula (a4-2B), *-A 43f -X 43 -R 43fB An example of the structure that the group represented by can take is the following structure (* is the bonding site with the carbonyl group). TIFF2025091391000116.tif14169

[0148] Examples of the structural unit represented by formula (a4-2A) include the following structural units and the structural units in which the methyl group corresponding to R in the structural unit represented by formula (a4-2A) below is replaced by a hydrogen atom. 41 are mentioned. TIFF2025091391000117.tif99167

[0149] Examples of the structural unit represented by formula (a4-2B) include the following structural units and structural units in which the methyl group corresponding to R in the following structural units is replaced by a hydrogen atom. 41 Examples include structural units in which the methyl group corresponding to R in the structural unit represented by formula (a4-2B) is replaced by a hydrogen atom. JPEG2025091391000118.jpg111163

[0150] Examples of the structural unit (a4) also include the structural unit represented by formula (a4-3). TIFF2025091391000119.tif5576[In formula (a4-3), R 41 represents a hydrogen atom or a methyl group. L 44f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. R 44f represents a saturated hydrocarbon group having 1 to 20 carbon atoms which may have a fluorine atom, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O- or -CO-. However, at least one of 44f L 44f and 44f R 44f has a fluorine atom, and the upper limit of the total number of carbon atoms of

[0151] L 44f and 44f R 44f and 44f R 44f and 44f R 42 in formula (a4) is 21.] L 44fis preferably an alkanediyl group having 1 to 14 carbon atoms (wherein -CH2- contained in the alkanediyl group may be replaced by -O- or -CO-), and -(CH2) j1 -, -(CH2) j2 -O-(CH2) j3 - or -(CH2) j4 -CO-O-(CH2) j5 - represented groups (j1 to j5 each independently represent an integer from 1 to 6). It is more preferable. Further, an alkanediyl group having 1 to 4 carbon atoms (one -CH2- contained in the alkanediyl group may be replaced by -O-, and one -CH2-CH2- contained in the alkanediyl group may be replaced by -CO-O- or -O-CO-) is even more preferable. R 44f is preferably a saturated hydrocarbon group having 1 to 10 carbon atoms having a fluorine atom, more preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom, an alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms having a fluorine atom or a group combining them, still more preferably an alkyl group having 1 to 10 carbon atoms having a fluorine atom, and even more preferably an alkyl group having 1 to 6 carbon atoms having a fluorine atom.

[0152] As the structural unit represented by the formula (a4-3), for example, in the following structural units and the structural units represented by the following formulas, the methyl group corresponding to R in the structural unit (a4-3) is replaced by a hydrogen atom. 41 Structural units can be mentioned. TIFF2025091391000120.tif86165

[0153] TIFF2025091391000121.tif3686[In the formula (a4-A), R 1 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X 11 represents a single bond or *-CO-O-. * represents the bonding site with the carbon atom to which R 1 is bonded. L 1represents an aliphatic hydrocarbon group having 1 to 28 carbon atoms which may have a substituent, and -CH2- contained in the aliphatic hydrocarbon group may be replaced by -O-, -S-, -SO2- or -CO-. R 2 represents a perfluoroalkyl group having 1 to 8 carbon atoms. R 3 represents a hydrogen atom or a perfluoroalkyl group having 1 to 6 carbon atoms, and the perfluoroalkyl group may combine with L 1 to form an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O-. mi represents any integer from 1 to 4. When mi is 2 or more, the groups in multiple parentheses may be the same as or different from each other.

[0154] R 1 Examples of the halogen atom and the alkyl group which may have a halogen atom in R a01 are the same as those exemplified by R a4 and R a5 in Formula (a1-0) to Formula (a1-2). R 1 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0155] L 1 Examples of the aliphatic hydrocarbon group in L include a chain hydrocarbon group, a monocyclic or polycyclic (including a spiro ring, a condensed ring, a bridged ring, etc.) alicyclic hydrocarbon group, and a group formed by combining two or more of these groups (for example, a hydrocarbon group formed from an alicyclic hydrocarbon group and a chain hydrocarbon group) may also be used. Examples of the alkanediyl group include linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, and heptadecane-1,17-diyl group, and branched alkanediyl groups such as ethane-1,1-diyl group, propane-1,1-diyl group, propane-1,2-diyl group, propane-2,2-diyl group, pentane-2,4-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, and 2-methylbutane-1,4-diyl group. Examples also include groups in which one or more hydrogen atoms of the above-described groups are replaced with a bonding site. The number of carbon atoms of the chain hydrocarbon group is preferably from 1 to 18, more preferably from 1 to 12, still more preferably from 1 to 10, even more preferably from 1 to 9, still even more preferably from 1 to 8, still more preferably from 1 to 6, still even more preferably from 1 to 5, and particularly preferably from 1 to 4.

[0156] Examples of the monocyclic or polycyclic alicyclic hydrocarbon group include the following alicyclic hydrocarbon groups. The bonding site can be at any position. TIFF2025091391000122.tif46163For example, divalent to pentavalent alicyclic hydrocarbon groups such as cycloalkanediyl group, cycloalkanetriyl group, cycloalkanetetrayl group, and cycloalkanepentayl group. Specifically, monocyclic alicyclic hydrocarbon groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, and cyclooctane-1,5-diyl group, and Examples of the polycyclic alicyclic hydrocarbon group include a spiro ring having a cycloalkanediyl group such as a norbornane-1,4-diyl group, a norbornane-2,5-diyl group, an adamantane-1,5-diyl group, an adamantane-2,6-diyl group, a decahydronaphthalenediyl group, a bicyclo[3.3.0]octanediyl group, a spirocyclohexane-1,2'-cyclopentane-diyl group, a spiroadamantane-2,3'-cyclopentane-diyl group, etc., a norbornanediyl group or an adamantanediyl group, and a cycloalkanediyl group spiro-bonded thereto respectively. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 20, more preferably 3 to 18, still more preferably 3 to 16, and even more preferably 3 to 12.

[0157] Examples of the group formed by combining two or more types include a group formed by combining an alicyclic hydrocarbon group and a chain hydrocarbon group. In the combination, the alicyclic hydrocarbon group and the chain hydrocarbon group may each be combined with two or more types. Also, any group may be bonded to X 11 . Examples of a group combining an alicyclic hydrocarbon group and a chain hydrocarbon group include a group in which an alicyclic hydrocarbon group is bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which a chain hydrocarbon group is bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-), a group in which an alicyclic hydrocarbon group and a chain hydrocarbon group are bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-), a group in which a chain hydrocarbon group and an alicyclic hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which an alicyclic hydrocarbon group, a chain hydrocarbon group, and an alicyclic hydrocarbon group are bonded to a chain hydrocarbon group (e.g., *-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-), a group in which a chain hydrocarbon group, an alicyclic hydrocarbon group, and a chain hydrocarbon group are bonded to an alicyclic hydrocarbon group (e.g., *-alicyclic hydrocarbon group-chain hydrocarbon group-alicyclic hydrocarbon group-chain hydrocarbon group-), and the like. * represents the bonding site to X. 11 Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced with a bonding site.

[0158] L 1 The -CH2- contained in the aliphatic hydrocarbon group having 1 to 28 carbon atoms of L may be replaced with -O-, -S-, -SO2- or -CO-. L 1 When the -CH2- contained in the aliphatic hydrocarbon group having 1 to 28 carbon atoms of L is replaced with -O-, -S-, -SO2- or -CO-, the number of carbon atoms before replacement is regarded as the number of carbon atoms of the aliphatic hydrocarbon group. Examples of the group in which -CH2- contained in the aliphatic hydrocarbon group is replaced by -O-, -S-, -SO2- or -CO- include a hydroxy group, a carboxy group, a thiol group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an oxy group, a carbonyl group, a thio group, a sulfonyl group, an alkanedioxy group, an alkanedioxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, an alkanediylsulfonyl group, an alkanediylthio group, a cycloalkoxy group, a cycloalkylalkoxy group, an alkoxycarbonyloxy group, a group formed by combining two or more of these groups, and the like. These replaced groups include those similar to the groups exemplified herein within the range allowed by the upper limit of the number of carbon atoms. Examples also include a group in which one or more hydrogen atoms of the above-described group are replaced by a bonding site. Examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O-, -S-, -CO- or -SO2- include those similar to the groups exemplified herein within the range allowed by the upper limit of the number of carbon atoms.

[0159] L 1 The aliphatic hydrocarbon group in L may have one or more substituents. Examples of the substituent include a halogen atom, a haloalkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms (wherein -CH2- contained in the alkyl group or the alicyclic hydrocarbon group may be replaced by -O- or -CO-). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. The haloalkyl groups having 1 to 4 carbon atoms include fluoroalkyl groups having 1 to 4 carbon atoms, chloroalkyl groups having 1 to 4 carbon atoms, bromoalkyl groups having 1 to 4 carbon atoms, iodoalkyl groups having 1 to 4 carbon atoms, and the like. Examples of the haloalkyl group include perfluoroalkyl groups having 1 to 4 carbon atoms (such as trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, nonafluorobutyl group, etc.), 2,2,2-trifluoroethyl group, 3,3,3-trifluoropropyl group, 4,4,4-trifluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, chloromethyl group, bromomethyl group, iodomethyl group, and the like. The number of carbon atoms of the haloalkyl group is preferably 1 to 3, more preferably 1 or 2. Examples of the alkyl group having 1 to 12 carbon atoms include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, and the like. The number of carbon atoms of the alkyl group is preferably 1 to 9, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. Examples of the alicyclic hydrocarbon group having 3 to 18 carbon atoms include monocyclic cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclodecyl group, and polycyclic cycloalkyl groups such as decahydronaphthyl group, adamantyl group, norbornyl group, and the like. The number of carbon atoms of the alicyclic hydrocarbon group is preferably 3 to 16, more preferably 3 to 12, and still more preferably 3 to 10. Examples of the aromatic hydrocarbon group having 6 to 18 carbon atoms include phenyl group, naphthyl group, biphenyl group, anthryl group, phenanthryl group, binaphthyl group, and the like. The number of carbon atoms of the aromatic hydrocarbon group is preferably 6 to 14, more preferably 6 to 12, and still more preferably 6 to 10. When -CH2- contained in an alkyl group is replaced by -O- or -CO-, the number of carbon atoms before replacement is defined as the total number of carbon atoms of the alkyl group. Examples of the replaced group include a hydroxy group, a carboxy group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, etc. These replaced groups include those similar to the groups exemplified in this specification as long as the upper limit of the number of carbon atoms permits. The number of carbon atoms of the alkoxy group is preferably 1 to 9, more preferably 1 to 6, still more preferably 1 to 4, and even more preferably 1 to 3. The number of carbon atoms of the alkoxycarbonyl group is preferably 2 to 9, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyl group is preferably 2 to 10, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. The number of carbon atoms of the alkylcarbonyloxy group is preferably 2 to 9, more preferably 2 to 6, still more preferably 2 to 4, and even more preferably 2 or 3. In addition, examples of the group in which -CH2- contained in the alicyclic hydrocarbon group is replaced by -O- or -CO- include those similar to the groups exemplified in this specification as long as the upper limit of the number of carbon atoms permits. L 1 The substituent that the aliphatic hydrocarbon group in L may have includes a halogen atom, a haloalkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms (wherein -CH2- contained in the alkyl group or the alicyclic hydrocarbon group may be replaced by -O- or -CO-). Preferably, it includes a fluorine atom, an iodine atom, a perfluoroalkyl group having 1 to 3 carbon atoms, or an alkyl group having 1 to 4 carbon atoms (wherein -CH2- contained in the alkyl group may be replaced by -O- or -CO-). More preferably, it includes a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, a hydroxy group, or a methoxy group. L 1 is R 3When it does not form an alkyl fluoride group and an alicyclic hydrocarbon group, it may have a substituent and a chain hydrocarbon group having 1 to 12 carbon atoms (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-), or a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms which may have a substituent and an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-, and the -CH2- contained in the alicyclic hydrocarbon group may be replaced by -O- or -CO-), preferably a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 3 to 12 carbon atoms which may have a substituent, or a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms which may have a substituent and an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), more preferably a chain hydrocarbon group having 1 to 8 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent, a group formed by combining a chain hydrocarbon group having 1 to 6 carbon atoms and an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), or a group formed by combining an alicyclic hydrocarbon group having 5 to 12 carbon atoms, a chain hydrocarbon group having 1 to 6 carbon atoms, and an alicyclic hydrocarbon group having 5 to 12 carbon atoms which may have a substituent (the -CH2- contained in the chain hydrocarbon group may be replaced by -O- or -CO-), even more preferably.

[0160] R 2Examples of the C1-C8 fluoroalkyl group include difluoromethyl group, trifluoromethyl group, 1,1-difluoroethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, perfluoroethyl group, 1,1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1-(trifluoromethyl)-1,2,2,2-tetrafluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3,3-hexafluorobutyl group, 1,1,2,2,3,3,4,4-octafluorobutyl group, perfluorobutyl group, 1,1-bis(trifluoro)methyl-2,2,2-trifluoroethyl group, 2-(perfluoropropyl)ethyl group, 1,1,2,2,3,3,4,4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3,3,4,4,5,5-decafluoropentyl group, 1,1-bis(trifluoromethyl)-2,2,3,3,3-pentafluoropropyl group, perfluoropentyl group, 2-(perfluorobutyl)ethyl group, 1,1,2,2,3,3,4,4,5,5-decafluorohexyl group, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl group, perfluoropentylmethyl group, perfluorohexyl group, perfluoroheptyl group, perfluorooctyl group. The carbon number of the fluoroalkyl group is preferably 1-6, more preferably 1-5, still more preferably 1-4, and even more preferably 1-3. R 3 The C1-C6 fluoroalkyl group in is, as long as the upper limit of the carbon number permits, the same as the C1-C6 fluoroalkyl group exemplified in the examples of the fluoroalkyl group of R 2 R 2 is preferably a C1-C6 fluoroalkyl group, more preferably a C1-C3 fluoroalkyl group, still more preferably a trifluoromethyl group, a perfluoroethyl group or a perfluoropropyl group, and even more preferably a trifluoromethyl group when R 3 is a C1-C6 fluoroalkyl group. R2 is, when R 3 is a hydrogen atom, preferably an alkyl fluoride group having 1 to 6 carbon atoms, more preferably an alkyl fluoride group having 1 to 5 carbon atoms, and still more preferably an alkyl fluoride group having 3 to 5 carbon atoms. R 3 is L 1 and combines to form an alicyclic hydrocarbon group having 3 to 12 carbon atoms, R 3 is L 1 Examples of the group formed by combining with include groups represented by the following formulas. In the following formulas, * and ** represent bonding sites, and two ** represent that one represents the bonding site with a hydroxy group and the other represents the bonding site with R 2 and, L 1A is, L 1 is a part of the hydrocarbon group of, and represents a single bond or an alkanediyl group having 1 to 4 carbon atoms. R 3 is L 1 The number of carbon atoms of the alicyclic hydrocarbon group formed by combining with is preferably 3 to 10, more preferably 3 to 8, and still more preferably 3 to 6. TIFF2025091391000123.tif25130R 3 is preferably a hydrogen atom or an alkyl fluoride group having 1 to 3 carbon atoms. mi is preferably any integer from 1 to 3, more preferably 1 or 2, and still more preferably 1.

[0161] Examples of the structural unit (a4-A) include the following structural units and the like. In these structural units, structural units in which the methyl group corresponding to R 1 is replaced with a hydrogen atom, a halogen atom, a haloalkyl group or an alkyl group other than a methyl group and structural units in which the hydrogen atom corresponding to R 1 is replaced with a halogen atom, a haloalkyl group or an alkyl group can also be cited as specific examples of the structural unit (a4-A). TIFF2025091391000124.tif192167

[0162] In the above structural units, R 1A structural unit in which the methyl group corresponding to is replaced with a hydrogen atom, a halogen atom, a haloalkyl group, or an alkyl group other than a methyl group, and R 1 Structural units in which the hydrogen atom corresponding to is replaced with a halogen atom, a haloalkyl group, or an alkyl group can also be cited as specific examples of the structural unit (a4-A).

[0163] When the resin (A) contains the structural unit (a4), its content is preferably 1 to 20 mol%, more preferably 2 to 15 mol%, and even more preferably 3 to 10 mol% with respect to all the structural units of the resin (A).

[0164] 〈Structural unit (a5)〉 Examples of the non-leaving hydrocarbon group possessed by the structural unit (a5) include groups having a linear, branched, or cyclic hydrocarbon group. Among them, the structural unit (a5) is preferably a group having an alicyclic hydrocarbon group. Examples of the structural unit (a5) include a structural unit represented by the formula (a5-1). TIFF2025091391000125.tif3971[In the formula (a5-1), R 51 represents a hydrogen atom or a methyl group. R 52 represents an alicyclic hydrocarbon group having 3 to 18 carbon atoms, and the hydrogen atoms contained in the alicyclic hydrocarbon group may be substituted with aliphatic hydrocarbon groups having 1 to 8 carbon atoms. L 55 represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and the -CH2- contained in the saturated hydrocarbon group may be replaced with -O- or -CO-.]

[0165] R 52 The alicyclic hydrocarbon group in may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic hydrocarbon group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Examples of the polycyclic alicyclic hydrocarbon group include an adamantyl group and a norbornyl group, etc. The aliphatic hydrocarbon group having 1 to 8 carbon atoms includes, for example, alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group. Examples of the alicyclic hydrocarbon group having a substituent include 3-methyladamantyl group. R 52 is preferably an unsubstituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, more preferably an adamantyl group, a norbornyl group or a cyclohexyl group. L 55 Examples of the divalent saturated hydrocarbon group in L include a divalent chain saturated hydrocarbon group and a divalent alicyclic saturated hydrocarbon group, and preferably a divalent chain saturated hydrocarbon group. Examples of the divalent chain saturated hydrocarbon group include alkanediyl groups such as methylene group, ethylene group, propanediyl group, butanediyl group and pentanediyl group. The divalent alicyclic saturated hydrocarbon group may be either monocyclic or polycyclic. Examples of the monocyclic alicyclic saturated hydrocarbon group include cycloalkanediyl groups such as cyclopentanediyl group and cyclohexanediyl group. Examples of the polycyclic divalent alicyclic saturated hydrocarbon group include adamantanediyl group and norbornanediyl group.

[0166] L 55 Examples of the group in which -CH2- contained in the divalent saturated hydrocarbon group represented by L is replaced by -O- or -CO- include the groups represented by formula (L1-1) to formula (L1-4). In the following formulas, * and ** each represent a bonding site, and * represents a bonding site with an oxygen atom. TIFF2025091391000126.tif18165[In formula (L1-1), X x1 represents *-O-CO- or *-CO-O- (* represents a bonding site with L x1 .). L x1 represents a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. L x2represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. However, the total number of carbon atoms in L x1 and L x2 is 16 or less. In formula (L1-2), L x3 represents a divalent aliphatic saturated hydrocarbon group having 1 to 17 carbon atoms. L x4 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 16 carbon atoms. However, the total number of carbon atoms in L x3 and L x4 is 17 or less. In formula (L1-3), L x5 represents a divalent aliphatic saturated hydrocarbon group having 1 to 15 carbon atoms. L x6 and L x7 each independently represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 14 carbon atoms. However, the total number of carbon atoms in L x5 , L x6 and L x7 is 15 or less. In formula (L1-4), L x8 and L x9 each represent a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms. W x1 represents a divalent alicyclic saturated hydrocarbon group having 3 to 15 carbon atoms. However, the total number of carbon atoms in L x8 , L x9 and W x1 is 15 or less. L x1 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x2 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond. L x3 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x4is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x5 is preferably a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x6 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a methylene group or an ethylene group. L x7 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms. L x8 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. L x9 is preferably a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 8 carbon atoms, more preferably a single bond or a methylene group. W x1 is preferably a divalent alicyclic saturated hydrocarbon group having 3 to 10 carbon atoms, more preferably a cyclohexanediyl group or an adamantanediyl group.

[0167] Examples of the group represented by the formula (L1-1) include, for example, the following divalent groups. TIFF2025091391000127.tif37148 Examples of the group represented by the formula (L1-2) include, for example, the following divalent groups. TIFF2025091391000128.tif23130 Examples of the group represented by the formula (L1-3) include, for example, the following divalent groups. TIFF2025091391000129.tif15147 Examples of the group represented by the formula (L1-4) include, for example, the following divalent groups. TIFF2025091391000130.tif13168L 55 is preferably a single bond or a group represented by the formula (L1-1).

[0168] As the structural unit (a5-1), there are the following structural units and the structural units in the structural unit (a5-1) in the following structural units where the methyl group corresponding to R 51 is replaced by a hydrogen atom. TIFF2025091391000131.tif111150 When the resin (A) contains the structural unit (a5), its content is preferably 1 to 30 mol%, more preferably 2 to 20 mol%, and even more preferably 3 to 15 mol% based on all the structural units of the resin (A).

[0169] 〈Structural unit (a6)〉 The structural unit (a6) is a structural unit having a -SO2- group, and preferably has a -SO2- group in the side chain. The structural unit having a -SO2- group may have a linear structure having a -SO2- group, a branched structure having a -SO2- group, or a cyclic structure (monocyclic and polycyclic structures) having a -SO2- group. Preferably, it is a structural unit having a cyclic structure having a -SO2- group, and more preferably, it is a structural unit having a cyclic structure (sultone ring) containing -SO2-O-.

[0170] As the sultone ring, the following formula (T 1 -1), formula (T 1 -2), formula (T 1 -3) and formula (T 1 -4). The bonding site can be at any position. The sultone ring may be monocyclic, but is preferably polycyclic. The polycyclic sultone ring means a bridged ring containing -SO2-O- as an atomic group constituting the ring, and examples include the rings represented by formula (T 1 -1) and formula (T 1 -2). The sultone ring may further contain a hetero atom in addition to -SO2-O- as an atomic group constituting the ring, like the ring represented by formula (T 1 -2). Examples of the hetero atom include an oxygen atom, a sulfur atom or a nitrogen atom, and preferably an oxygen atom. TIFF2025091391000132.tif2977

[0171] The sultone ring may have a substituent, and examples of the substituent include an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, and an alkylcarbonyl group having 2 to 4 carbon atoms.

[0172] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, and a decyl group, preferably an alkyl group having 1 to 6 carbon atoms, and more preferably a methyl group. Examples of the alkyl group having a halogen atom include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluoro sec-butyl group, a perfluoro tert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group, and preferably a trifluoromethyl group. Examples of the alkyl group having a hydroxy group include a hydroxymethyl group and a hydroxyalkyl group such as a 2-hydroxyethyl group. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, a decyloxy group, and a dodecyloxy group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a p-methylphenyl group, a p-tert-butylphenyl group, a p-adamantylphenyl group, a tolyl group, a xylyl group, a cumyl group, a mesityl group, a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group. Examples of the aralkyl group include benzyl group, phenethyl group, phenylpropyl group, naphthylmethyl group, and naphthylethyl group. Examples of the alkoxycarbonyl group include a group in which an alkoxy group such as a methoxycarbonyl group or an ethoxycarbonyl group is bonded to a carbonyl group, preferably an alkoxycarbonyl group having 6 or less carbon atoms, and more preferably a methoxycarbonyl group. Examples of the alkylcarbonyl group include acetyl group, propionyl group, and butyryl group. From the viewpoint that the production of the monomer leading to the structural unit (a6) is easy, a sultone ring having no substituent is preferred.

[0173] As the sultone ring, a ring represented by the following formula (T1') is preferred. TIFF2025091391000133.tif2665[In the formula (T1'), X 11 represents an oxygen atom, a sulfur atom, or a methylene group. R 41 represents an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group, a halogen atom, a hydroxy group, a cyano group, an alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a glycidyloxy group, an alkoxycarbonyl group having 2 to 12 carbon atoms, or an alkylcarbonyl group having 2 to 4 carbon atoms. ma represents any integer from 0 to 9. When ma is 2 or more, a plurality of R 41 may be the same or different. The bonding site is at an arbitrary position.] X 11 is preferably an oxygen atom or a methylene group, and more preferably a methylene group. R 41 is the same as those of the substituent of the sultone ring, and an alkyl group having 1 to 12 carbon atoms which may have a halogen atom or a hydroxy group is preferred. ma is preferably 0 or 1, and more preferably 0.

[0174] Examples of the ring represented by formula (T1’) include the following rings. The bonding site can be at any position. Among them, those in which the bonding site is at the 1-position or 3-position are preferred. TIFF2025091391000134.tif44148

[0175] The structural unit having a -SO2- group preferably further has a group derived from a polymerizable group. Examples of the polymerizable group include a vinyl group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, an acryloylamino group, a methacryloylamino group, an acryloylthio group, a methacryloylthio group, and the like. Among them, the monomer that leads to the structural unit (a6) is preferably a monomer having an ethylenically unsaturated bond, and more preferably a (meth)acrylic monomer.

[0176] The structural unit (a6) is preferably a structural unit represented by formula (a6-0). TIFF2025091391000135.tif4077[In formula (a6-0), R x represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom. A xx represents an oxygen atom, -N(R c )-, or a sulfur atom. A x represents a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms, and -CH2- contained in the saturated hydrocarbon group may be replaced by -O-, -CO-, or -N(R d ). X 11 represents an oxygen atom, a sulfur atom, or a methylene group. R 41 represents the same group as described above. ma represents any integer from 0 to 9. When ma is 2 or more, a plurality of R 41 may be the same or different. R c and R dEach independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

[0177] R x Examples of the halogen atom of x include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R x Examples of the alkyl group of x include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, and an n-hexyl group, etc. Preferably, it is an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group. R x Examples of the alkyl group having a halogen atom of x include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, a perfluorohexyl group, a trichloromethyl group, a tribromomethyl group, and a triiodomethyl group, etc. R x Preferably, it is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group. A x Examples of the divalent saturated hydrocarbon group of x include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic divalent alicyclic saturated hydrocarbon group, and those obtained by combining two or more of these groups may also be used. Specifically, linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane-1,17-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group and propane-2,2-diyl group; Branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group; Monocyclic divalent alicyclic saturated hydrocarbon groups which are cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; Polycyclic divalent alicyclic saturated hydrocarbon groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. can be mentioned. A x The bonding position to the sultone ring of can be any position, but the one at the 1-position is preferred.

[0178] Examples of the structural unit (a6-0) include the following structural units. TIFF2025091391000136.tif93150Among them, the structural units represented by formula (a6-1), formula (a6-2), formula (a6-6), formula (a6-7), formula (a6-8) and formula (a6-12) are preferred, and the structural units represented by formula (a6-1), formula (a6-2), formula (a6-7) and (a6-8) are more preferred. When the resin (A) contains the structural unit (a6), its content is preferably 1 to 50 mol%, more preferably 2 to 40 mol%, and still more preferably 3 to 30 mol% based on all the structural units of the resin (A).

[0179] <Structural unit (a7)> The resin (A) may further contain a structural unit that decomposes upon exposure to generate an acid (hereinafter sometimes referred to as "structural unit (a7)"). Specific examples of the structural unit (a7) include the structural units described in JP-A-2016-79235, and it is preferably a structural unit having a sulfonate group or a carboxylate group and an organic cation in the side chain or a structural unit having a sulfonio group and an organic anion in the side chain.

[0180] The structural unit having a sulfonate group or a carboxylate group and an organic cation in the side chain is preferably a structural unit represented by the formula (a7-A). TIFF2025091391000137.tif35107[In the formula (a7-A), R a7 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. X a71 represents a single bond, *-O-*, *-CO-O-*, *-O-CO-O-*, *-CO-NR a71 -*, *-NR a71 -CO-O-*, *-O-CO-NR a71 -* or *-Ax-Ph-Ay-*. R a71 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Ph represents a phenylene group which may have a substituent. Ax and Ay each independently represent one or more bond types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amide bond, and a carbonate ester bond. * and ** represent bonding sites, and * represents the bonding site with the carbon atom to which R a7 is bonded. L a71and L a72 each independently represents a hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and -CH2- contained in the hydrocarbon group may be replaced by -O-, -S-, -CO- or -SO2-. X a72 represents ***-CO-O-, ***-O-CO-, ***-O-CO-O-, ***-O-, where *** is L a71 and represents the bonding site with na7 represents any integer from 0 to 2. When na7 is 2, the groups in the plurality of parentheses may be the same as or different from each other. RA - represents a sulfonate anion or a carboxylate anion. ZA + represents an organic cation.]

[0181] R a7 Examples of the halogen atom and the alkyl group having 1 to 6 carbon atoms which may have a halogen atom in R are the same as those exemplified by R of formula (a1-0). a01 and the like can be mentioned. R a7 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom or a methyl group.

[0182] X a71 When X is a group represented by *-Ax-Ph-Ay-**, it is preferably a linking group represented by the following formula (X10). TIFF2025091391000138.tif3351[In formula (X10), Ax represents the bonding species that binds to the carbon atom to which R a7 is bonded, and represents one or more bonding species selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, a carbonate ester bond and an amide bond. Ay is L a71Represents a bonding type that binds to, and represents one or more bonding types selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, a carbonate bond, and an amide bond. Rx represents a halogen atom, a hydroxy group, a C1-C6 fluoroalkyl group, a C1-C18 alkyl group, or a C1-C6 alkoxy group. mx represents any integer from 0 to 4, and when mx is an integer of 2 or more, the plurality of Rx may be the same as or different from each other. When either Ax or Ay is a single bond, the other is preferably one or more selected from the group consisting of an ether bond, a thioether bond, an ester bond, a carbonate bond, and an amide bond. When either Ax or Ay is an amide bond, it is preferably a bond represented by -CO-NR a71 - represented by. The bonding position of Ay in the phenylene group is preferably the m-position or the p-position with respect to the bonding position of Ax, and more preferably the p-position. Among them, Rx is preferably a fluorine atom, an iodine atom, a trifluoromethyl group, a methyl group, or an ethyl group. mx is preferably 0, 1, or 2. X a71 As, for example, a single bond, the following formula (X 10 -1) to formula (X 10 -10) groups represented by. * is -R a7 Represents the bonding site with the carbon atom to which it binds. ** represents the bonding site with L a71 Represents. X 20 Represents -O- or -NR a71 -. TIFF2025091391000139.tif44162 Formula (X 10 -1) to formula (X 10 -10) Specific examples of the groups represented by include the following groups. TIFF2025091391000140.tif87163 Among them, X 10 Is a single bond or formula (X 10 -1') and formula (X 10 -3') to formula (X10 It is preferably a group represented by any of them, a single bond or formula (X 10 -1'), formula (X 10 -4'), formula (X 10 -5'), formula (X 10 -6') and formula (X 10 -10'), more preferably a single bond, a group represented by formula (X 10 -1'), a group represented by formula (X 10 -5') or a group represented by formula (X 10 -6').

[0183] L a71 Examples of the hydrocarbon group of include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining two or more of these groups, with one hydrogen atom removed, and a group that binds to X a71 and X a72 . Further, examples of the hydrocarbon group of L a72 include a chain hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining two or more of these groups, with one hydrogen atom removed, and a group that binds to X a72 and RA - . L a71 and L a72 Examples of the chain hydrocarbon group of include a group obtained by removing one hydrogen atom from an alkyl group or an alkenyl group. The alkyl group may be linear or branched, and specifically includes a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, an iso-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a heptadecyl group, etc. Examples of the alkenyl group include an ethenyl group, a propenyl group, an isopropenyl group, a butenyl group, an isobutenyl group, a tert-butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, an isooctenyl group, a nonenyl group, etc. The number of carbon atoms in the chain hydrocarbon group is preferably 1 to 20, more preferably 1 to 18, and even more preferably 1 to 10. L a71 and L a72 Examples of the alicyclic hydrocarbon group of L and L include a group obtained by removing one hydrogen atom from a monocyclic or polycyclic cycloalkyl group. Examples of the monocyclic cycloalkyl group include a cyclobutyl group, a cycloheptyl group, a cyclohexyl group, a cyclopentyl group, a cyclooctyl group, and the like. L a71 and L a72 Examples of the polycyclic cycloalkyl group of L and L include a cycloalkyl group having a crosslinked structure, a cycloalkyl group in which two or more rings are condensed, or a cycloalkyl group in which two rings are spiro-bonded. Examples of the cycloalkyl group having a crosslinked structure include a norbornyl group, an adamantyl group, and the like. Examples of the cycloalkyl group in which two or more rings are condensed include a bicyclo[4,4,0]decane group, a steroid group (steroid skeleton), and the like. Examples of the cycloalkyl group in which two rings are spiro-bonded include a spirocyclic cycloalkyl group in which one cycloalkyl group selected from the group consisting of a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group and a cycloalkyl group having 5 to 8 carbon atoms are spiro-bonded. A double bond may be formed between two carbon atoms contained in the alicyclic hydrocarbon group. More specifically, the alicyclic hydrocarbon group represented by the following formula can be mentioned. TIFF2025091391000141.tif28158 When the alicyclic hydrocarbon group is a monocyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 3 to 18, more preferably 3 to 12, and even more preferably 3 to 8. When the alicyclic hydrocarbon group is a polycyclic cycloalkyl group, the number of carbon atoms in the alicyclic hydrocarbon group is preferably 6 to 18, more preferably 7 to 12. L a71 and L a72Examples of the aromatic hydrocarbon group include a group formed by removing one hydrogen atom from an aryl group. Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a fluorenyl group, etc. The number of carbon atoms in the aromatic hydrocarbon group is preferably 5 to 14, more preferably 6 to 14, and even more preferably 6 to 10. L a71 and L a72 When -CH2- contained in the hydrocarbon group of a72 is replaced by -O-, -CO-, -S- or -SO2-, the number of carbon atoms before replacement is defined as the number of carbon atoms of the hydrocarbon group. L a71 and L a72 Examples of the group in which -CH2- contained in the chain hydrocarbon group among the hydrocarbon groups of a72 is replaced by -O-, -CO-, -S- or -SO2- include a hydroxy group, a carboxy group, a thiol group, a carbonyl group, an oxy group, a thio group, a sulfonyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkanedioxy group, an alkanedioxycarbonyl group, an alkanediylcarbonyl group, an alkanediylcarbonyloxy group, etc. These replaced groups include those similar to the groups exemplified in this specification within the range where the upper limit of the number of carbon atoms permits. L a71 and L a72 Examples of the group in which -CH2- contained in the alicyclic hydrocarbon group among the hydrocarbon groups of a72 is replaced by -O-, -CO-, -S- or -SO2- include a group containing a cyclic ether, a cyclic ketone, a cyclic ester (lactone), a cyclic thioether, a cyclic acetal, a cyclic sulfonic acid ester (sultone) structure, etc. Specifically, alicyclic hydrocarbon groups represented by the following formulas are included. The bonding position of the alicyclic hydrocarbon groups listed in the following formulas can be any position. TIFF2025091391000142.tif46146L a71 and L a72Among the hydrocarbon groups, -CH2- contained in the aromatic hydrocarbon group may be replaced by -O- or -S-. Examples of the group in which -CH2- is replaced by -O- or -S- include groups derived from a furan ring or a thiophene ring, respectively. L a71 and L a72 Examples of the group formed by combining two or more of the chain hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group of a72 include the group formed by combining the above chain hydrocarbon group and the above alicyclic hydrocarbon group, the group formed by combining the above chain hydrocarbon group and the above aromatic hydrocarbon group, the group formed by combining the above alicyclic hydrocarbon group and the above aromatic hydrocarbon group, and the group formed by combining the above chain hydrocarbon group, the above alicyclic hydrocarbon group, and the above aromatic hydrocarbon group. The group formed by combining the alicyclic hydrocarbon group and the aromatic hydrocarbon group may be a condensed ring. L a71 and L a72 Examples of the substituent that the hydrocarbon group of a72 may have include a halogen atom, a cyano group, and a nitro group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. L a71 and L a72 When a72 is a group formed by combining an alicyclic hydrocarbon group or an aromatic hydrocarbon group with a chain hydrocarbon group, the chain hydrocarbon group may be substantially regarded as a substituent that the alicyclic hydrocarbon group or the aromatic hydrocarbon group has. Also, L a71 and L a72 By replacing -CH2- of the chain hydrocarbon group contained in the hydrocarbon group of a72 with -O-, -CO-, -S-, or -SO2-, L a71 and L a72 The hydrocarbon group of a72 may substantially have substituents such as a hydroxy group, a carboxy group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, a thiol group, and a sulfonyl group. na7 is preferably 0 or 1. ZA in formula (a7-A) + is the same as the cation in the salt represented by formula (B1) and the like.

[0184] In formula (a7-A), L a71 and L a72 are saturated hydrocarbon groups, in formula (a7-B) described later, A b7 may contain a group similar to the group exemplified as the divalent linking group. Examples of the structural unit represented by formula (a7-A) include the structural unit represented by formula (a7-A1). TIFF2025091391000143.tif30138[In formula (a7-A1), R a7 、X a71 、L a71 、X a72 、na7、RA - and ZA + have the same meanings as described above. z7 represents any integer from 0 to 6. Q a7 、Q b7 、R z71 and R z72 each independently represent a hydrogen atom, a fluorine atom, a perfluoroalkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 6 carbon atoms. When z7 is 2 or more, a plurality of R z71 and R z72 may be the same as or different from each other.] Q a7 、Q b7 、R z71 and R z72 Examples of the perfluoroalkyl group having 1 to 6 carbon atoms or the alkyl group having 1 to 6 carbon atoms in include groups similar to the groups exemplified for R a7 .

[0185] Examples of the structural unit represented by formula (a7-A) include, for example, the following structural units, groups corresponding to the methyl group of R a7 replaced with a hydrogen atom, a halogen atom (for example, a fluorine atom), or an alkyl group having 1 to 6 carbon atoms that may have a halogen atom (for example, a trifluoromethyl group, etc.), and the structural units described in International Publication No. 2012 / 050015. ZA + represents an organic cation. TIFF2025091391000144.tif244163

[0186] TIFF2025091391000145.tif131157

[0187] The structural unit having a sulfonio group and an organic anion in the side chain is preferably a structural unit represented by the formula (a7-B). TIFF2025091391000146.tif28104[In the formula (a7-B), R a7 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. A b7 represents a single bond or a divalent linking group. R b71 represents a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent. R b72 and R b73 each independently represent a hydrocarbon group having 1 to 18 carbon atoms which may have a substituent, and R b72 and R b73 may combine with each other to form a ring together with the sulfur atom to which they are attached. A - represents an organic anion.] R a7 Examples of the halogen atom of R and the alkyl group which may have a halogen atom include the same halogen atoms and alkyl groups which may have a halogen atom as those in the formula (a7-A). R b71 Examples of the divalent aromatic hydrocarbon group having 6 to 18 carbon atoms represented by include a phenylene group and a naphthylene group. R b72 and R b73 Examples of the hydrocarbon group represented by include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group formed by combining these. Examples of the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, and a group formed by combining these include the same as those described above. Ab7 Examples of the divalent linking group represented by the formula include divalent saturated hydrocarbon groups having 1 to 18 carbon atoms, and -CH2- contained in the divalent saturated hydrocarbon group may be replaced by -O-, -S- or -CO-. Examples of the divalent saturated hydrocarbon group include divalent chain saturated hydrocarbon groups such as linear or branched alkanediyl groups, and monocyclic or polycyclic divalent alicyclic saturated hydrocarbon groups, and combinations thereof may also be used. Specifically, linear alkanediyl groups such as methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl group, dodecane-1,12-diyl group; branched alkanediyl groups such as butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4-diyl group, 2-methylbutane-1,4-diyl group; divalent monocyclic alicyclic saturated hydrocarbon groups which are monocyclic cycloalkanediyl groups such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group; divalent polycyclic alicyclic saturated hydrocarbon groups which are polycyclic cycloalkanediyl groups such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. Examples of those in which -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S- or -CO- include the following divalent groups. However, the number of carbon atoms before -CH2- contained in the saturated hydrocarbon group is replaced by -O-, -S- or -CO- is 17 or less, respectively. In the following formula, * and ** represent bonding sites, and * represents the bonding site with R b71 and represents the bonding site with. TIFF2025091391000147.tif123161[wherein X 3 represents a divalent saturated hydrocarbon group having 1 to 16 carbon atoms. X4 represents a divalent saturated hydrocarbon group having 1 to 15 carbon atoms. X 5 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms. X 6 represents a divalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 7 represents a trivalent saturated hydrocarbon group having 1 to 14 carbon atoms. X 8 represents a divalent saturated hydrocarbon group having 1 to 13 carbon atoms.

[0188] Examples of the structural unit containing the cation in formula (a7-B) include the structural unit represented below and a group corresponding to the methyl group of R a7 in which the methyl group is replaced with a hydrogen atom, a halogen atom (for example, a fluorine atom), or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom (for example, a trifluoromethyl group, etc.). TIFF2025091391000148.tif75163

[0189] A - Examples of the organic anion represented by A include a sulfonate anion, a sulfonylimide anion, a sulfonylmethide anion, and a carboxylate anion. A - The organic anion represented by A is preferably a sulfonate anion, and more preferably the same as the anion exemplified by the acid generator (B). Examples of the sulfonylimide anion, the sulfonylmethide anion, and the carboxylate anion are the same as the anions exemplified by the acid generator (B).

[0190] Examples of the structural unit represented by formula (a7-B) include the structural unit represented below. JPEG2025091391000149.jpg95156

[0191] When the resin (A) contains the structural unit (a7), the structural unit (a7) may be contained alone or in combination of two or more. The total content ratio of the structural unit (a7) is preferably 1 to 30 mol%, more preferably 1 to 25 mol%, still more preferably 2 to 20 mol%, even more preferably 3 to 15 mol%, and even more preferably 3 to 10 mol% based on all the structural units of the resin (A).

[0192] The resin (A) is preferably a resin composed of the structural unit (II) and the structural unit (a1), or a resin composed of the structural unit (II), the structural unit (a1) and the structural unit (s). The structural unit (a1) is preferably at least one selected from the gr...

Claims

1. An acid generator containing a salt represented by formula (I); A resist composition comprising a resin that comprises a structural unit represented by formula (II) and a structural unit having an acid labile group. [In formula (I), X represents a sulfur atom or an iodine atom. m10 represents 0 or 1, and when X is a sulfur atom, m10 is 1, and when X is an iodine atom, m10 is 0. R １ , R ２ and R ３ each independently represents a linear alkyl group having 2 to 12 carbon atoms. R ４ , R ５ and R ６ each independently represents a halogen atom or a hydrocarbon group having 1 to 18 carbon atoms, the hydrocarbon group optionally having a substituent, 2 - is -O-, -CO-, -S-, -SO- or -SO ２ It may be replaced by -. R ７ , R ８ and R ９ each independently represents a halogen atom or a hydrocarbon group having 1 to 18 carbon atoms, the hydrocarbon group optionally having a substituent, 2 - is -O-, -CO-, -S-, -SO- or -SO ２ When X is a sulfur atom, R ７ and R ８ Or R ８ and R ９ is bonded to S ＋ The ring may contain —CH 2 - is -O-, -S-, -CO-, -SO- or -SO ２ R forming the ring may be replaced with -. ７ and R ８ Or R ８ and R ９ , S ＋ and a single bond formed between two benzene rings connecting the two. A １ , A ２ and A ３ each independently represents a single bond or a hydrocarbon group having 1 to 20 carbon atoms, the hydrocarbon group optionally having a substituent, 2 - is -O-, -CO-, -S- or -SO ２ It may be replaced by -. Ar １ , Ar ２ and Ar ３ each independently represents an aromatic hydrocarbon group having 6 to 10 carbon atoms or a heterocyclic aromatic hydrocarbon group having 4 to 9 carbon atoms. m1 represents an integer of 0 to 5, and when m1 is 2 or more, the groups in multiple parentheses may be the same or different. m2 represents an integer of 0 to 5, and when m2 is 2 or more, the groups in the parentheses may be the same or different. m3 represents an integer of 0 to 5, and when m3 is 2 or more, the groups in the parentheses may be the same or different. m4 represents an integer of 0 to 4, and when m4 is 2 or more, a plurality of R ４ may be the same or different from each other. m5 represents an integer of 0 to 4, and when m5 is 2 or more, a plurality of R ５ may be the same or different from each other. m6 represents an integer of 0 to 4, and when m6 is 2 or more, a plurality of R ６ may be the same or different from each other. m7 represents an integer of 0 to 5, and when m7 is 2 or more, a plurality of R ７ may be the same or different from each other. m8 represents an integer of 0 to 5, and when m8 is 2 or more, a plurality of R ８ may be the same or different from each other. m9 represents an integer of 0 to 5, and when m9 is 2 or more, a plurality of R ９ may be the same or different from each other. However, 1≦m1+m7≦5, 1≦m2+m8≦5, 1≦m3+m9≦5, and when m1=m2=m3=0, R ７ , R ８ and R ９ represents a linear alkyl group having 2 to 12 carbon atoms. AI － represents an organic anion. [In formula (II), R １２ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom, or a halogen atom. L １１ is a single bond or *-L ２ -CO-O-(L ３ -CO-O) ｇ -. * represents the bonding site with an oxygen atom. L ２ and L ３ each independently represents a divalent hydrocarbon group having 1 to 12 carbon atoms. g represents 0 or 1. R １３ represents a linear alkyl group having 2 to 12 carbon atoms.

2. A １ But, **-X ０１ -L ０１ - or **-L ０１ -X ０１ - and A ２ But, **-X ０２ -L ０２ - or **-L ０２ -X ０２ - and A ３ But, **-X ０３ -L ０３ - or **-L ０３ -X ０３ - and X ０１ , X ０２ and X ０３ each independently represents -O-, -CO-, -S- or -SO ２ - represents L ０１ , L ０２ and L ０３ each independently represents a single bond or a hydrocarbon group having 1 to 18 carbon atoms (the hydrocarbon group may have a substituent, and the —CH 2 - is -O-, -CO-, -S- or -SO ２ - may be replaced by . ** is X ＋ 2. The resist composition according to claim 1, wherein the bond site to the benzene ring is

3. X ０１ , X ０２ and X ０３ The resist composition according to claim 2, wherein each of the groups independently represents --O-- or --S--.

4. L ０１ , L ０２ and L ０３ each independently represents a single bond or an alkanediyl group having 1 to 6 carbon atoms (the —CH 2 3. The resist composition according to claim 2, wherein - may be replaced by -O- or -CO-.

5. 3. The resist composition according to claim 1, wherein X is a sulfur atom.

6. Ar １ , Ar ２ and Ar ３ 3. The resist composition according to claim 1, wherein each of the groups independently represents a group derived from a benzene ring, a naphthalene ring, a furan ring, or a thiophene ring.

7. L １１ 3. The resist composition according to claim 1, wherein: is a single bond.

8. R １３ 3. The resist composition according to claim 1, wherein is a straight-chain alkyl group having 3 to 8 carbon atoms.

9. 3. The resist composition according to claim 1, wherein the structural unit having an acid labile group includes at least one selected from the group consisting of a structural unit represented by formula (a1-0), a structural unit represented by formula (a1-1), a structural unit represented by formula (a1-2), a structural unit represented by formula (a1-4), a structural unit represented by formula (a1-5), and a structural unit represented by formula (a1-6). [In formula (a1-0), formula (a1-1) and formula (a1-2), L ａ０１ , L ａ１ and L ａ２ are each independently -O- or *-O-(CH ２ ) ｋ１ represents --CO--O--, k1 represents an integer of 1 to 7, and * represents the bonding site with --CO--. R ａ０１ , R ａ４ and R ａ５ each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ０２ , R ａ０３ and R ａ０４ each independently represents an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a combination thereof, and the alkyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may contain a halogen atom. R ａ６ and R ａ７ each independently represents an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group formed by combining these, and the alkyl group, alkenyl group, alicyclic hydrocarbon group and aromatic hydrocarbon group may have a halogen atom. m1 represents an integer of 0 to 14. n1 represents an integer of 0 to 10. n1' represents an integer of 0 to 3. [In formula (a1-4), R ａ１ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R ａ１７ represents a halogen atom, a hydroxy group, a carboxy group, an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group, or a methacryloyloxy group. A ａ１１ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and the —CH ２ - is -O-, -CO- or -NR ａ１８ May be replaced with -. R ａ１８ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X ａ１ represents a single bond or a carbonyl group. R a34 and R a35 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms; R a36 represents a hydrocarbon group having 1 to 20 carbon atoms, or R a35 and R a36 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms together with the -C-O- to which they are bonded, and the hydrocarbon group and the -CH 2 - may be replaced by -O- or -S-. na1 represents an integer of 1 to 5, and when na1 is 2 or more, the groups in the parentheses may be the same or different. na11 represents an integer of 0 to 4, and when na11 is 2 or more, a plurality of R ａ１７ may be the same or different from each other. mc represents an integer of 0 to 2. [In formula (a1-5), R a8 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom. Z a1 is a single bond or *-(CH 2 ) h3 -CO-L 54 -, h3 represents an integer of 1 to 4, * represents L 51 represents the binding site with L 51 , L 52 , L 53 and L 54 each independently represents --O-- or --S--. s1 represents an integer of 1 to 3. s1′ represents an integer of 0 to 3.] [In formula (a1-6), R a61 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom. R a6２ , R a63 and R a6４ each independently represents an alkyl group having 1 to 6 carbon atoms or a cyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, or R a6２ and R a63 are bonded to each other to form, together with the carbon atoms to which they are attached, a ring having 3 to 20 carbon atoms. X a61 is a single bond, -CO-O-* or -CO-NR a65 - represents *, * represents a bonding site with Ar, R a65 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X a62 is a single bond, *-O-L a61 - or *-CO-O-L a62 -, * represents a bonding site with Ar, L a61 and L a62 each independently represents an alkanediyl group having 1 to 4 carbon atoms. Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent.]

10. AI － 3. The resist composition according to claim 1, wherein the anion is represented by formula (IA). [In formula (IA), L b1 represents a single bond or a (nb1+1)-valent hydrocarbon group which may have a substituent, and —CH 2 - is -O-, -S-, -CO- or -SO 2 It may be replaced by -. L b2 represents a single bond or a divalent hydrocarbon group having 1 to 24 carbon atoms which may have a substituent, and the —CH 2 - is -O-, -S-, -CO- or -SO 2 It may be replaced with -. Y b1 represents a methyl group which may have a substituent or a cyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and —CH 2 - is -O-, -S-, -CO- or -SO 2 It may be replaced with -. nb1 represents an integer of 1 to 6. When nb1 is 2 or more, the groups in the parentheses may be the same or different.

11. 3. The resist composition according to claim 1, further comprising a salt capable of generating an acid having a weaker acidity than the acid generated from the acid generator.

12. (1) a step of applying the resist composition according to claim 1 or 2 onto a substrate; (2) A step of drying the applied resist composition to form a composition layer; (3) exposing the composition layer to light; (4) heating the composition layer after exposure; and (5) developing the composition layer after heating; A method for producing a resist pattern comprising the steps of:

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